Zac Baillie / AFP - Getty Images

A Syrian rebel covers a fellow fighter carrying the body of his brother, killed during a battle in the Saif al-Dawla district of Syria's northern city of Aleppo, amid heavy street fighting between opposition and government forces on August 29, 2012.

First, he reprimanded me for not calling enough and hardly visiting. I’ve been away too long. You can’t do that, not to your friends. What’s so difficult about calling? he asked.

I apologized, asked about his children, his health, if he’s having success in quitting smoking, and offered the only excuse I could think of: "I’ve been busy with the Arab Spring."

"The Arab Spring?" he said. "What’s that? There’s no Arab Spring anymore. That’s over. It is now a big struggle for power." 

He may have been acting like an insistent grandmother, but he was right. The Arab Spring is over. The days of the protesters with laptops and BlackBerrys in Tahrir Square are long gone.

Instead, a much bigger struggle is underway, one that goes back centuries that is both a regional battle for dominance and an epic tug of war between Sunnis and Shiites for control of the Middle East and the Prophet Muhammad's legacy.

The front line is now in Syria, where the United Nations says more than 20,000 people have been killed since pro-democracy protests started in March 2011.

But it goes back, at least in very modern history, at least to Iraq — and America shares a large part of the responsibility for reopening this Pandora’s Box.

Roots in Iraq
A major factor in the rise of the present struggle came when American troops invaded Iraq in 2003, thus pitting Sunnis against their rival Shiites, who many Sunnis think are effectively infidels who turned against Islamic leaders about 1,400 years ago and have been on the wrong side of Allah’s path since then.

For decades, Saddam and his Sunni minority had imposed their will on Iraq, carrying on a 14-century tradition of Sunnis controlling Mesopotamia despite a Shiite majority. Not surprisingly, in most Sunni regions there has little appetite for free U.S.-sponsored elections. They knew they would end up being ruled by their enemies.

And that’s what happened. Essentially, the lasting legacy of America’s involvement in Iraq is an Iranian-allied Shiite government that also happens to be one of the most corrupt on the planet. (Iran is the biggest and most powerful Shiite-majority nation.) 

Reuters

Iran's religious breakdown by Shiite and Sunni Muslims. Iran is 89 percent Shiite Muslim and approximately 10 percent Sunni. But the rest of the region is predominately Sunni Muslim. There are more than 1 billion Sunnis worldwide, making up 87-90 percent of the global Muslim population. Click on the map to see a larger version.

The Shiites were, of course, delighted. I remember the moment U.S. troops left their last base in southern Iraq in December 2011.  The Iraqis changed its name as the Americans rolled out the gate. It had been called Camp Adder; the Iraqis renamed it 'the Imam Ali base,' after the patriarch of Shiite Islam.

The Shiites — in both Iraq and Iran — won, and won big.  

President George W. Bush, in his now-rare public appearances and interviews, still refuses to acknowledge he did anything to help Iran. But it doesn’t really matter what he thinks. The 200 million people in the Middle East understand that there is a new reality — and that’s what they are battling about now. 

Iraqi Sunnis are still seething — and sometimes fighting — in their stronghold cities of Ramadi and Fallujah.  They can’t accept what they consider the tragedy that has befallen their community and don’t understand even now why Washington sent troops across the Atlantic and Indian oceans to help Iran expand a buffer zone beyond its borders.

Enter al-Qaida, a radical Sunni group
Back in the Iraq war days, al-Qaida, a radical Sunni group, saw an opportunity to expand. Al-Qaida militants flowed to Iraq to help fellow Sunnis fight Iran, Shiites and the Americans who were propping them up. But al-Qaida got more than it bargained for. The U.S. troops were tougher than al-Qaida expected. American forces learned guerilla tactics in Iraq. They built bigger, stronger vehicles to defeat car bombs and IEDs. U.S. troops, much to al-Qaida surprise and dismay, moved at night, dropped men from helicopters like spiders and blasted militant safe houses into kindling.

Al-Qaida made another mistake too. It misbehaved in Iraq and abused its hosts, fellow Sunni tribesmen. Al-Qaida forgot it was a guest and abandoned its manners. Al-Qaida killed Sunni tribesmen because they weren’t fundamentalist enough. The wild-eyed militants flogged Sunnis in Ramadi and Fallujah for minor infractions like taking off their pants to swim in the Euphrates. It was hardly the behavior of someone who’s claiming to help.

The Americans eventually used al-Qaida’s misbehavior against the group, forming a militia of Sunnis who were fed up with the fanatics, often referred to as the "Sons of Iraq." Al-Qaida lost in Iraq and the Shiite government won. Iran won, too. 

After the Shiites came to power in Baghdad, Iran suddenly had access to Iraq’s holy Shiite cities of Najaf and Karbala. Iran increased tourism and business ties with its new Shiite-controlled neighbor. The majority of passengers now arriving and departing from Baghdad International Airport are from Iran.

Photo Blog: Portraits from the front line: Syrian rebels pose in Aleppo

Syria, Lebanon, Hezbollah
Of course, it isn’t tourism that is on the minds of concerned observers of the Middle East. Rather, it is another Shiite government — just to the northwest of Iraq —the Syrian regime of President Bashar al-Assad.

In fact, the Assad family isn’t actually Shiite, but Alawite, a secretive Shiite-linked offshoot that makes up just about 13 percent of the population. There’s also a sizable Christian community. Iran has effectively adopted the Alawites into the family by forging a long-standing alliance with Assad and — before him — his father, Hafez, who ruled Syria from 1971-1990.   

Reuters

A breakdown of religious groups in Syria. Approximately 70 percent of Syria's population is Sunni Muslim. About 3 percent are Shiite, but another 12.8 percent are Alawite, a Shiite offshoot that President Bashar al-Assad follows. Click on the map to see a larger version.

And, moving further west from Syria, there’s Lebanon. Lebanon is a mixed basket if there ever was one. It’s Sunni in the north, Christian in the middle and Shiite in the south, with each making up about a third of the population. As any Lebanese person will tell you, it’s a volatile mix that has produced a lively culture, fantastic food, attractive people — and recurring cycles of civil war. 

Topping the heap in Lebanon are the Shiites, emboldened by their powerful and skilled militia, Hezbollah. Hezbollah is heavily armed and has thousands of rockets pointed at Israel. The weapons mostly come from Iran through Syria or from Syria itself. In addition, Hezbollah runs a powerful social network. It can collapse the Lebanese government when it chooses.  

France sends aid, cash to rebel-held Syrian cities, source says

So, there we have it. The previously isolated Shiite regime in Iran is emboldened by the emergence of a Shiite-dominated government in Iraq. In reaction, the Sunni world becomes concerned about the upstart Shiite powers, complete with their considerable oil resources and weaponry.

The region, already a tinderbox, becomes primed for a power struggle.

At the same time, there is the matter of religious pride and a sense of being in the right. In the Muslim world, the Sunnis are the big players. There are more than 1 billion Sunnis worldwide — making up 87-90 percent of the world’s total Muslim population, according to the Pew Research Center. By comparison, Shiites are a relatively small group, there are just about 150-200 million Shiites in the world, with about 75 percent living in just four countries: Iran, Iraq, Pakistan and India, according to Pew. 

For the world’s Sunni Muslims, there is a certain confidence, perhaps even arrogance, that comes with having a billion friends. 

Arab Spring shake-up
At first, the current unrest was unrelated to the Sunni-Shiite divide. The first eruption came in Tunisia, which exploded in protests in December 2010. Then came Egypt, Bahrain, Libya and Yemen.

The region’s dictators were caught off guard by student demonstrators who had mobile communications that government security forces couldn’t track or monitor. The students could organize flash mobs. They could communicate directly with hundreds of millions of supporters though social media. 

The Arab regimes in 2011 in many ways were legacies of Israel’s victories in 1948 and 1967. Faced with the catastrophic defeats, military strongmen grew in power. Over time they become corrupt. By 2011, most Arab governments were brutal, uncreative and thoroughly uninspiring.

In Tunisia, lawyers, students and women’s groups protested in because of the country’s secret prisons and because the former president’s wife was taking a cut of nearly everyone’s business.  

The Egyptian regime was similarly ossified and out of touch. Hosni Mubarak had been an effective president in his early years and relatively popular. But by the time protests began in Cairo’s Tahrir Square, he was 82 years old, his military cohorts and family had become increasingly corrupt, he had been president for nearly three decades, and he was insistent that his bland son take over from him.

The Arab Spring put the Middle East back in flux — and, encapsulated by the current situation in Syria — put religious divides back in the spotlight.

The rise of religious tensions started in Egypt, where the Islamist Muslim Brotherhood — a Sunni organization — mobilized and easily hijacked the 2011 revolution started by liberals, anarchists, socialists, students, artists and techno-nerds who were joined by millions of the unemployed and disenfranchised. Sunni Islamists, albeit moderate, took over in Tunisia, too.

Slideshow: Syria uprising

Goran Tomasevic / Reuters

After months of protests and violent crackdowns, a look back at the violence that has overtaken the country.

Launch slideshow

But it is Syria that has become the epicenter of the historic battle between Sunnis and Shiites. And Lebanon will probably follow.

I spoke with a rebel in Syria about a month ago who explained the religious calculation.

"We lost Iraq to the Shiites and Iran. We’re going to take Syria for us," he said. 

Nearly all of the rebels in Syria are Sunnis and the fighting in Syria remains almost exclusively in Sunni areas. Alawite areas remain generally supportive of the Assad regime and therefore haven’t been attacked by the central government. The worst massacres have taken place in Sunni villages that are surrounded by Alawite towns.

The rebels claim the Alawites want to drive out Sunnis from their areas to make pure Alawite blocks for self-defense in case they lose the war and are hunted. Although the rebels say they want to create a Sunni-led government, which they promise will be open and democratic, this isn’t Tahrir Square anymore.  It’s not even close.

Iran-Syria alliance
The Syrian government has long found Iran and Hezbollah to be useful allies. Iran is technologically advanced and offers a big market for Syrian goods. Hezbollah is a sword Damascus can wave over Israel's head, and a way to maintain influence in Lebanon, which Syria claims (with some reason) was historically part of Syria before the horribly planned British and French division of the Middle East during and after World War I.

U.S. officials: Iran supplying Syrian military via Iraqi airspace

But war changes the dynamics between allies.  As Assad’s grip on power weakens, Iran and Hezbollah’s position in Syria grows stronger. The tail is starting to wag the dog. Iranian and Hezbollah advisers are becoming increasingly dominant in Syria.

U.S. Defense Secretary Leon Panetta spoke out publicly about Iran’s increasing presence in Syria last month.  

"There’s now an indication that they’re trying to develop or trying to train a militia within Syria to be able to fight on behalf of the regime," Panetta said at a Pentagon news briefing. "So we are seeing a growing presence by Iran and that is of deep concern to us."

In Syria, I saw evidence of Hezbollah’s influence at an army outpost that the rebels had just taken over. Rebels claimed there were 20 Hezbollah fighters in the outpost. They said that they occupied their own room and fought to the death. I saw boxes of unpacked Hezbollah flags.

It’s no longer a situation where Hezbollah is just providing arms and intelligence, but appears to have mobilized and is fighting alongside Syrian forces.

Youssef Boudlal / Reuters

Free Syrian Army fighters from Qadissiya Brigade detain two Syrian army soldiers in the El Amriyeh neighbourhood of Syria's northwestern city of Aleppo in Sept. 4, 2012.

And al-Qaida is also trying to make up for lost time. Its leader is dead and Afghanistan and Pakistan aren’t as safe as they used to be. Even Yemen is unsafe with increasing American drone strikes. Al-Qaida trying to do in Syria what it failed to accomplish in Iraq.  Al-Qaida has learned from its Iraq’s experience. Sensing an opening, al-Qaida fighters are going into Syria offering money and arms to the rebels, their Sunni brothers.

They are going in politely, or at least as politely as al-Qaida can be. They are offering rebels cash with no strings attached, at first.  Initial payments tend to be small, around $5,000. It is tiny sum in a war zone, but enough to give strapped rebel units a taste of what’s to come. They also have RPGs, the weapon rebel commanders seem to value above all others. 

After taking a few payments, according to rebels who’ve seen this process, al-Qaida fighters — from Algeria, Iraq, Libya, Chechnya and other countries — ask that the rebels receive some of their men. An increasingly number of rebels commanders are taking the deal, even though they worry what al-Qaida could ask for in the future. 

They reason that it’s better to take the support than die with nothing. Without American troops to worry about — not even drones —Syria could prove to be a far better base for al-Qaida than Iraq ever was.

What’s next?
What happens if Washington continues to watch from afar?

Well, Syria is likely to become an even bigger battleground for a proxy war between Hezbollah, Sunni rebels, government troops, Iran and al-Qaida. And once Syria collapses — or even before — Lebanon could ignite as well. 

My Iraqi friend was right. The Arab Spring no longer exists.  

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