ROBERT SIEGEL, HOST:
The Arab Spring has brought large-scale protests and violence to at least half a dozen countries in the last three years. Until now, the U.S. has intervened militarily in one of those countries, Libya.
As President Obama considers a strike on Syria, NPR's Ari Shapiro explores the differences between the two scenarios.
ARI SHAPIRO, BYLINE: When President Obama first announced U.S. military action in Libya, he highlighted a few facts he felt sure of at the time.
PRESIDENT BARACK OBAMA: In this effort, the United States is acting with a broad coalition that is committed to enforcing United Nations Security Council Resolution 1973, which calls for the protection of the Libyan people.
SHAPIRO: Russia and China did not block U.N. action on Libya.
That was then. Today, Russia is loudly defending Syria. Two years ago, the Arab League supported the mission to take out Moammar Gadhafi. Today, the league does not support an attack on Bashar al-Assad.
Paul Salem directs the Carnegie Middle East Center in Beirut.
PAUL SALEM: Nobody regionally and nobody internationally stood by Gadhafi and his regime. Obviously, Syria is very different. Syria has Iran, the Maliki government in Iraq, Russia, China and Hezbollah in support of it.
SHAPIRO: A chart showing who supports which side in Syria's civil war looks like a bowl of spaghetti. Add to that the fears that any conflict with Syria will look like a proxy war, say, between Iran and the United States.
Amos Guiora is at the University of Utah law school.
AMOS GUIORA: Syria is very important from the perspective of geopolitics. Syria presents for the Iranian navy the ability to dock in Syrian ports and to sail in the Mediterranean.
SHAPIRO: And don't forget that Israel - America's number one Mideast ally - is in Syria's backyard. So from a global perspective, the situation in Syria is far more complicated than it was in Libya. And there are big differences between Libya and Syria internally as well. The people in Libya are almost all Sunni Arabs. But in Syria, many different religious groups live in an often uneasy mix.
Mark Katz of George Mason University says, start with the government. It's run by minority Alawites, an offshoot of Shiite Islam.
MARK KATZ: But there are so many other communities. The country consists of a majority of Sunni Arabs, there are Kurds, there are Arab Christians, there are Druze. And these other minorities are also fearful that a change to Sunni majority rule will have a negative impact on them.
SHAPIRO: And the rebels themselves are far less cohesive in Syria than they were in Libya. Remember, the U.S. recognized one rebel government in Libya. In Syria, it's not even clear how many groups there are. Some experts say dozens, others say almost a thousand. Here's something most experts do agree on.
JOSHUA LANDIS: The most powerful ones are Salafists and jihadists. Some are linked to Al-Qaida.
SHAPIRO: Joshua Landis directs the Center for Middle East Studies at the University of Oklahoma.
LANDIS: Libya's a country of 6 million people, and it can already pay its own bills. Syria is a country of 24 million. Almost a third of them, 7 million, have been displaced - 2 million outside the country, 5 million internally - and the economy is in shambles.
SHAPIRO: Libya can pay its own bills because it's the largest oil producer in Africa. Syria doesn't have nearly as much oil as its neighbors. That means reconstruction would be much more expensive.
Finally, there's a difference in the U.S. mission. In Libya, President Obama and his allies sought to take out Moammar Gadhafi. In Syria, the president described the U.S. goal as preventing the use of chemical weapons. He spoke last night on PBS.
OBAMA: If we are saying in a clear and decisive but very limited way, we send a shot across the bow saying, stop doing this, that can have a positive impact on our national security over the long term.
SHAPIRO: In Libya, the U.S. ended its military involvement after seven months when Moammar Gadhafi was killed. In Syria, it's still not clear what sort of military involvement the U.S. might wage or how long it could last.
Ari Shapiro, NPR News, Washington.