If it had to happen, it couldn't have happened at a better time.

That terrible assessment has to govern the U.S. reaction to the news yesterday that Syria's Assad regime has once again used chemical weapons against its own people. According to the BBC's reportage, at least 58 Syrian civilians are dead in Idlib and even more injured. Syrian jets, according to activists and NGO's followed up the attack by targeting hospitals.

So what else is new? And, be it noted, the leftist media has immediately rushed to blame the attack on the Trump administration and Secretary of State Rex Tillerson. That's malarkey, easy enough. But what, if anything, should the U.S. do?

Is this just another day in the ongoing cascade of war crimes and crimes against humanity in Syria's civil war? With at least 400,000 dead and at least 13.5 million Syrian refugees (6 million internally displaced persons and the rest mostly in Turkey and Europe), isn't the world's conscience and its willingness to stop this horror exhausted? Terrible, awful, but, you know, nothing can be done.

That, of course, is what the Obama administration did -- and said.

Wrong. Quite a lot can be done. In fact, there's a cascade of coincidences suggesting that an opportunity for a U-turn in American policy towards the Assad regime is being presented by this latest war crime.

First, there's a new American administration in Washington. Thus, a reversal of the Obama administration's policy carries little or no political cost. And requires no heavy lifting.

Press Secretary Sean Spicer set the new tone yesterday: "These heinous actions by the Bashar al-Assad regime are a consequence of the last administration's weakness and irresolution... President Obama said in 2012 that he would establish a 'red line' against the use of chemical weapons and then did nothing."

Correct.

Among President Obama's notable foreign policy failures was his refusal to act as the leader of the Free World. This was starkly illustrated by his abdication of American power in Syria in the wake of the Arab Spring. Most famously, having drawn a red-line against Syrian use of chemical weapons, Mr. Obama then walked away from that line when, in fact, the Assad regime crossed it.

Since then, as Walter Russell Meade has written, “the world has caught on fire.” This latest slaughter in Idlib is only the latest direct result of that failure.

Second, by coincidence, the United Nations Security Council in this month of April is being chaired by the United States. This means that Ambassador Nikki Haley -- who has been outspoken in her criticism of the Assad regime and its ally, Russia -- will be presiding over the Security Council. According to the website of the U.S. Permanent Mission to the United Nations, the United States, as President of the Security Council, “will be responsible for setting the agenda for the month, organizing meetings, managing the distribution of information to Council members, issuing statements, and communicating the Council’s actions to the public.”

In other words: the United States is temporarily in the driver's seat at the Security Council. And on Tuesday, France called for an emergency meeting of the Security Council to take up the latest Syrian atrocity. France, like the United States, the UK, Russia, and China, is a permanent member of the Security Council.

Each has the ability to veto strong action against the Assad regime.

Third, also by coincidence, Russia has just been hit by Islamic terror. And fourth, again, by coincidence, President Trump will be sitting down this weekend with the president of the Peoples Republic of China. Chinese support for decisive UN action against Assad should be on the agenda at Mar-a-Lago.

In short, all the diplomatic pieces are in place for decisive action on Syria if, once again, the United States is willing to lead. The time for mere sanctions is past. Relevant options include: a uniting-for-peace resolution, a referral of President Assad and his government to the International Criminal Court and creation of a Special Tribunal on war crimes and crimes against humanity in Syria.

Ambassador Haley said in her Sunday interviews that she is finding that her UN colleagues are glad to see that the United States is “back in the game.” At a press conference held to mark the commencement of her presidency of the Security Council, Haley said: "It's that we don't think the people want Assad anymore; we don't think that he is going to be someone that the people want to have. We have no love for Assad. We've made that very clear. We think that he has been a hindrance to peace for a long time. He's a war criminal. What he's done to his people is nothing more than disgusting."

Let us see if the other members of the Security Council are willing to welcome and support U.S. leadership again.