A rebel spokesman, who spoke from a “liberated area” held by the opposition in Damascus, told NBC News there were huge explosions just before 2 a.m. Sunday local time (7 p.m. Saturday ET) in the Qaysoun mountains on the edge of Damascus…

“Secondary explosions continued for about four hours. They shook all of Damascus. There was still smoke in the air as the sun came up.”

From its Damascus media office, the Free Syrian Army listed 9 apparent targets, including the Syrian Revolutionary Guard, the 104th brigade headquarters, a weapons depot in Qasyoun and a military research center at Jamraya…

The White House said there would be no official comment on the latest attack, but diplomatic sources and U.S. officials told NBC News that the administration is fully supportive of the airstrikes.

While the government tried to use the airstrikes to taint the rebels by linking them to Israel, Syria’s arch rival, the attacks still pose a dilemma for an Assad regime already battling a relentless rebellion at home. If it fails to respond, it looks weak and opens the door to such airstrikes becoming a common occurrence. But any military retaliation against Israel would risk dragging the Jewish state and its powerful army into a broader conflict.

The tempo of the new strikes added a dangerous dynamic to the conflict, fueling concerns that events could spin out of control and spark a regional crisis…

A senior Israeli official, who spoke on condition of anonymity in order to disclose information about a secret military operation to the media, confirmed that Israel launched an airstrike in the Syrian capital early Sunday but did not give more precise details about the location. The target was Fateh-110 missiles, which have precision guidance systems with better aim than anything Hezbollah is known to have in its arsenal, the official told The Associated Press.

[W]ow, this is awkward for the Syrian opposition. The regime will seek to exploit the raids to tie the rebels to the Zionist entity, after spending two years painting them as an undifferentiated mass of “terrorist gangs.” (Syrian television is already testing out this line, according to Reuters: “The new Israeli attack is an attempt to raise the morale of the terrorist groups which have been reeling from strikes by our noble army.”)

But the propaganda can cut both ways. The rebels can point to the Israeli attacks as yet more evidence that Assad’s army is for attacking Syrians, not defending the country. It’s not clear to me which argument will carry the day.

The strikes also promise to hypercharge the debate over Syria in the United States. Advocates of intervention will ask: If Syrian air defenses are so tough, as U.S. officials have been saying, why was Israel able to breach them so easily? Of course, a no-fly zone is a much more difficult and risky endeavor than a one-off raid, but you can expect that important distinction to get blurred.

There’s also a message here for Iran, whose nuclear program Israel has vowed to destroy if the Iranians cross Prime Minister Benjamin Netanyahu’s red line.

Israeli experts said that Israel had no interest in getting involved in the Syrian conflict beyond looking after Israel’s own, immediate interests, and that the latest strikes appeared to have more to do with Israel’s cardinal standoff against Iran.

“This shouldn’t be seen as Israel intervening on behalf of the rebels or against Bashar,” said Jonathan Spyer, a senior research fellow at the Interdisciplinary Center in Herzliya. “This is an escalation in a conflict we know about, and that is the conflict between Israel and Iran, the long shadow war, as people call it. This is an incident in that war.”…

Professor Moshe Maoz of the Hebrew University said that Iran was now the crucial actor regarding how things might unfold.

“If Hezbollah gets a green light from Iran to retaliate, Israel won’t remain idle and it could lead to regional war,” he said. “The decision is probably to be taken in Tehran.”

With the ‘right to protect’ based foreign policy now lying in ruins, Syria really is turning into a problem from hell for the White House. Whether considered from a humanitarian or a strategic point of view, all the choices are getting worse while the problem is becoming more important and harder to avoid…

1. Assad’s forces seem to be on the rebound militarily and are taking back some territory recently seized by the rebels…

2. But just because Assad is fighting smart doesn’t mean he’s not being brutal. The regime has been resorting to horrific levels of violence: a mix of retaliation, ethnic cleansing (to create a more secure Alawite base in the coastal area) and a deliberate use of terror to cow opponents. Case in point, there were fresh reports of a massacre this weekend in the coastal city of Banias. The source of this particular report was a pro-rebel group and so its numbers and details must be taken with a grain of salt, but overall there’s little reason to doubt that this kind of stuff is going on.

3. The reason for Assad’s recent success appears to be effective foreign support, especially from Iran. The most glaring evidence for this came this morning, with reports that Israel had struck a warehouse in Damascus full of advanced Iranian missiles intended ultimately for Hezbollah. This isn’t just a nasty local civil war. This isn’t just a broader Sunni-Shiite rivalry which threatens to spill over into Lebanon and Iraq. This is an important proxy battle for influence in the whole region, and Tehran is intimately involved. At the moment, it is defying the United States, the Sunni Arabs and western Europe, and it is succeeding.

The reports grew more disturbing, if still fragmentary, by the weekend of Aug. 18 and 19. Denis McDonough, then the president’s principal deputy national security adviser and now the White House chief of staff, coordinated a series of urgent classified meetings in the West Wing. “It was a catalyzing event,” said one official involved.

The advisers reviewed an array of pre-emptive military options and quickly discounted them as impractical. The evidence was not strong enough to warrant a pre-emptive strike, they concluded, and military officers said the best they could do with airstrikes or commando operations would be to limit the use of chemical weapons already deployed.

Mr. Obama’s advisers also raised legal issues. “How can we attack another country unless it’s in self-defense and with no Security Council resolution?” another official said, referring to United Nations authorization. “If he drops sarin on his own people, what’s that got to do with us?”

The administration’s ultimatum now seems like cheap talk, and it illustrates the risks of carelessly drawing red lines and issuing highly public threats that won’t be enforced.

So far, at least, the Obama administration has put off both consequences and accountability and simply pushed for further investigation. Meanwhile, Mr. Assad has not blinked, and the president’s political opponents, like Representative Mike Rogers, Republican of Michigan, argue that Iran and North Korea will draw the wrong lessons if the president lets Mr. Assad call his bluff…

In practice, red lines often create perverse incentives and encourage the enemy to continue aggression even as it avoids a red line. Declaring that the United States would act only if chemical weapons were used in Syria implied that we would tolerate other forms of violence. Indeed, Mr. Assad’s regime has killed over 80,000 of its own people, primarily using artillery and bullets, knowing that these forms of death are not covered by the specific public warning regarding chemical weapons…

If they can’t learn this lesson, public embarrassment, reduced credibility and more dead civilians are the likely results.

I believe if you want to end the Syrian civil war and tilt Syria onto a democratic path, you need an international force to occupy the entire country, secure the borders, disarm all the militias and midwife a transition to democracy. It would be staggeringly costly and take a long time, with the outcome still not guaranteed. But without a homegrown Syrian leader who can be a healer, not a divider, for all its communities, my view is that anything short of an external force that rebuilds Syria from the bottom up will fail. Since there are no countries volunteering for that role (and I am certainly not nominating the U.S.), my guess is that the fighting in Syria will continue until the parties get exhausted…

Here’s the one alternative that won’t happen: one side will decisively defeat the other and usher in peace that way. That is a fantasy.

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“Firstly, he never should have drawn the red line. Second of all, the red lines were a green light to Bassar al-Assad to do anything short of that,” McCain told Fox News’ Chris Wallace. ”Chemical weapons are terrible, but isn’t it pretty terrible when you launch scud missiles against your own people, when you massacre over 70,000 people, drive a million into refugee camps? Those seem to have been acceptable to this administration, and it’s deplorable.“