WASHINGTON (AP) — President Barack Obama's administration insists that Syrian President Bashar Assad's government carried out a chemical weapons attack last week against his own people, the latest turn in an ongoing conflict in the country. And Obama's team is laying the groundwork for an expected punitive military strike. But he's having trouble getting other countries to go along with him.
Assad's government denies the allegations and insists the rebels are to blame for any chemical attack, and Russia is among the countries lining up behind him.
Here's a look at the latest developments and how it got to this point:
THE SYRIAN CONFLICT
Now in its third year, the civil war in Syria — a small country with a population of about 23 million — is a complicated and brutal one with heavy civilian casualties on both sides.
The conflict has increasingly taken on sectarian tones as rebels, some of them Islamic extremists, fight government loyalists. It's essentially a regional proxy war that is increasingly being fought along sectarian lines, pitting Sunni against Shiite Muslims, and threatening the stability of Syria's neighbors.
By mid-2011, a loose coalition of rebels and anti-government tribal groups had formed the Free Syrian Army whose goal was to topple the Assad regime. As the violence increased, with those on both sides accused of killing civilians, more and more refugees fled the country.
Rebels appeared to be gaining the upper hand and they occupied more and more territory. But over the past few months the military scored a string of victories and their offensives pushed many rebels back into the Damascus suburbs.
The Assad regime increased its pressure on rebels as pro-democracy Arab Spring movements swept through the region last year.
The United Nations estimates that roughly 1.5 million people have now fled the country, many into Lebanon.
THE WORLD'S RESPONSE TO SYRIA'S CIVIL WAR BEFORE THE ALLEGED CHEMICAL ATTACK
Even before the alleged chemical attacks, the Assad regime was hit with an increasing number of sanctions from European countries and the U.S.
While the regime gained increasing support and supplies from Russia and Iran, the escalating sanctions by the European Union and the United States put more pressure on people struggling with food and fuel shortages and escalating inflation.
That may have contributed to fueling increasing unrest and violence.
OBAMA'S RED LINE AND EARLIER RESPONSE
Last summer, Obama said that Assad's use of chemical weapons would cross a red line, suggesting greater U.S. intervention. Then in June, the White House said it had conclusive evidence that Assad used chemical weapons against rebel fighters, and Obama decided to respond by authorizing the arming of Syria's rebels.
The move promised to deepen U.S. involvement in the conflict and heightening U.S. tensions with Russia, a staunch ally of Assad. It was a turning point for the U.S., which up to that point had avoided getting drawn into the conflict militarily. A key U.S. concern had been that U.S.-supplied weapons could fall into the hands of al-Qaida-linked militants fighting alongside the rebels.
THE TIPPING POINT
On Aug. 21, the Obama administration says, Assad's government unleashed a chemical attack outside Damascus, the capital. The government of Syria denies there were any chemical attacks. Syrian officials insist that rebels carried out the attacks. There's disagreement within the international community over whether there were chemical weapons used. And estimates of the dead have varied depending on the source.
Activists and those who live in the area have said well over 1,000 people died in the attacks. Secretary of State John Kerry put the death count at 1,429, of which he said 426 were children. However, the nonpartisan humanitarian group Doctors Without Borders has put the death toll at 355 people.
THE OBAMA ADMINISTRATION'S ARGUMENT
Obama says he hasn't made a final decision about a military strike against Syria. But he says he's considering a limited and narrow action in response to a chemical weapons attack that he says Syria's government carried out last week.
He made the comments after the U.S. released an intelligence assessment that found with "high confidence" that Assad's government carried out a chemical weapons attack last week.
But Obama has not yet been able to show that Assad himself ordered the attacks or spelled out how punishing military strikes might defer future use of chemical weapons in the region.
COALITION OF THE NOT-SO WILLING
It's been hard for Obama to assemble an international coalition to confront Syria. That's because burnout over long engagements in Iraq and Afghanistan, and the unpopularity of military adventures in Muslim countries, have wearied traditional Western allies.
Britain, a stalwart ally in the wars in Iraq and Afghanistan, won't play a direct role in any U.S. attack this time. British lawmakers abruptly refused to approve military action, despite a strong appeal by Prime Minister David Cameron to help the United States.
The only allied leader to openly express willingness to join a U.S. attack on Syria was French President Francois Hollande.
The German government also said it isn't considering joining military action against Syria.
A MATTER OF TIMING
It could be seen as rude for the president to order air strikes while U.N. weapons inspectors are still at work in Syria searching for evidence of chemical weapons use. They were expected to issue a report on their findings on Saturday at the earliest.
There's also a relatively short window before Obama leaves Tuesday on a foreign trip that will take him out of the country for most of next week — first to Sweden and then to St. Petersburg, Russia, for a meeting with the Group of 20 economic summit.
This year's host, Russian President Vladimir Putin, is a vocal opponent of a military strike in Syria. It seems unlikely that Obama would want to order air strikes on Syria while he's out of the country, especially on Putin's turf.
U.N. Secretary-General Ban Ki-moon planned to meet privately with the ambassadors of the five permanent Security Council members as part of his efforts to urge the divided council to come together and act on Syria's crisis. But Russia has veto power over Security Council proposals and is likely to exercise it if military strikes are contemplated.
CONGRESS, THE CONSTITUTION AND THE WAR POWERS ACT
There's little doubt that Obama as commander-in-chief could retaliate against Syrian targets without approval from the American people or their representatives in Congress. He's done it before — two years ago in Syria. So have many other U.S. presidents.
Even though the Constitution gives Congress the sole power to declare — and pay for — war, Congress hasn't formally declared war since World War II.
Every subsequent conflict involving U.S. forces, including military conflicts in Korea, Vietnam, Panama, Iraq (twice), the Caribbean island of Grenada, Kosovo and Libya were undeclared, even though in most cases Congress did vote approval short of a war declaration — sometimes after the fact.
The Korean War was fought under the auspices of the United Nations. The Kosovo War was waged by the North Atlantic Treaty Organization.
Congress' constitutional power to declare war was refined and expanded by the 1973 War Powers Act, which requires a president to notify Congress within 48 hours of initiating military action and bars U.S. armed forces for fighting for more than a maximum of 90 days without congressional approval.
HOW IT PROBABLY WOULD WORK
Obama has ruled out putting troops on the ground in Syria, and because of Assad's extensive air defense systems.
Any order for a strike would come from Obama, delivered to Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, and Defense Secretary Chuck Hagel. U.S. commanders would communicate and coordinate with military officers from other nations involved in the fight, such as France, over secure lines.
Five U.S. Navy destroyers are in the eastern Mediterranean Sea waiting for the order to launch. They are armed with dozens of Tomahawk cruise missiles. The Navy also now has two aircraft carriers in the Arabian Sea that are loaded with fighter jets.
THE DIFFERENT U.S. RESPONSES TO HUMANITARIAN CRISES IN RWANDA, KOSOVO AND SYRIA
Obama and his supporters have cited humanitarian motivations in setting the stage for military strikes in Syria, where more than 100,000 civilians have been killed in a civil war that has now lasted three years, including more than 300 deaths from chemical weapons attacks last week that the Obama administration blames on the Syrian government.
But the United States has a mixed record on responding to humanitarian crises. More than 500,000 people were killed in genocidal mass slaughter in 1994 in the East African state of Rwanda in a civil war between ethnic groups. The United States did not get involved militarily, although it later helped out in international efforts to relocate refugees.
Five years later, with President Bill Clinton still in the White House, it was a different story. As many as 10,000 ethnic Albanians were killed in Kosovo through the "ethnic cleansing" of Yugoslav leader Yugoslavia's Slobodan Milosevic. Clinton ordered air strikes that lasted 78 days.
Milosevic had the strong support of Russia, as Syria's Assad does today.
Obama has drawn several "red lines" that could put him in a box and make it difficult to compromise with opponents.
On Syria, he has said that Assad would cross one if he used chemical weapons in violation of international agreements that ban the use of them. And Syria's alleged use of chemical weapons tests the president's credibility on the world stage.
Obama drew another red line on Iran, saying it was unacceptable for that country to develop nuclear weapons.
Tehran has regularly warned the U.S. against possible military action against Syria, calling such a strike Iran's own "red line" even as a cruise-missile bearing U.S. naval fleet positions itself off Syria's coast. And Iranian President Hassan Rouhani said his country will press forward with efforts to ward off military action in Syria by the U.S. and its allies.
At home, Obama has also set ultimatums. He has said he won't negotiate with Republicans in Congress over raising the nation's debt ceiling, which the Treasury Department says will the hit in mid-October, and he's refused to consider any budget that includes the across-the-board, automatic spending cuts known as the sequester that went into effect in March.
Associated Press writers Donna Cassata, Julie Pace, Lolita Baldor, Josh Lederman and Connie Cass in Washington, Nasser Karimi in Tehran, Pablo Gorondi in Budapest, Hungary, Albert Aji in Damascus and Alexandra Olson at the United Nations contributed to this report.
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