US President Barack Obama's administration announced on Thursday (13.06.2013) that Washington would allow direct military support to the democratic groups among Syria's anti-government insurgents.

The reason behind the change of heart, explained Obama's deputy national security adviser Ben Rhodes, was the use of chemical weapons by Syrian President Bashar al-Assad's regime.

Obama last year had labeled their use as a 'red line', which, if crossed, would have serious consequences for the Syrian government.

According to Rhodes, Washington was now convinced after careful and thorough examination that Assad had indeed "used chemical weapons on a small scale against the opposition multiple times in the last year."

The accusations are not new. The first reports about chemical weapons being used in Syria began to circulate late last year. Then, in April of this year, France and Britain, followed by Israel, said they had evidence that the Assad regime had used chemical weapons.

Shortly thereafter, US Secretary of Defense Chuck Hagel said that Washington believed the Syrian regime had used chemical weapons against its own people. In early June, Paris and London reiterated their suspicions and shared their evidence with the White House.

Why now, Obama?

"He described the use of chemical weapons as a 'red line' several months ago and now he is on the spot to do something about it," explained Heinz Gärtner, a US expert at the Austrian Institute for International Affairs (OIIP) in Vienna. Domestically, says Gärtner, pressure has also been building from prominent Republicans, like John McCain, who want more than just the announced military support - for example, the implementation of a no-fly zone.

The growing domestic and international pressure on Obama to finally take action is, however, not the real reason for Obama's decision to intervene actively in the conflict, says Nathalie Tocci, deputy director of the Rome-based Institute for International Relations (IAI).

The suspected use of chemical weapons, after all, has been known for some time. "The trigger, in my view," says Tocci, "is that Assad's forces, with extensive help from Hezbollah, have now gained the upper hand."

Syria's rebel army has been considered badly damaged since it lost the battle for the city of Qusair in early June. At the end of May, the German intelligence service BND had already revised its estimate of the situation, saying that Assad's forces were advancing and were stronger than they had been for some time.

To avoid a further weakening or even the defeat of Assad's opponents before a second round of negotiations planned for the end of July, Obama needed to act, argues Tocci, otherwise there would be no reason for Assad to participate in the talks.

New phase

The conflict is on the verge of a new phase of direct US military assistance, initially implemented by the CIA. "Because delivering weapons through allies has not worked, the next step is to try the direct delivery of arms," stressed OIIP's Gärtner.

For the experts it is clear that the planned arms deliveries will escalate the war, but not decide it.

"This is not a game changer," said Tocci, adding that Washington was aware of this. "The goal is to try to re-establish a balance of power. If they had wanted a game changer, they would have imposed a no-fly zone."

Wrong hands

At the moment, at least, Washington is not ready to go that far. But even direct arms deliveries are risky, because, as experts point out, one can never be totally certain where those weapons will end up. Weapons that the US sent to the Afghan Mujahideen in the 1980s to fight the Soviets, for example, were later used against US forces. It is not known what weaponry the US intends to send to Syrian rebels, but the intention is clearly to strengthen the opposition significantly, perhaps with shoulder-launched surface-to-air missiles.

"One could expect that some of these arms deliveries will end up with groups who are fighting Assad, but who could also use these weapons against the West later," says Gärtner. "When you deliver surface-to-air missiles they could, one day, be used by terrorists against civilian passenger planes. All-in-all, it is a highly problematic idea just to deliver weapons to the good guys."