WASHINGTON — The Syrian refugee debate has become a national embarrassment. It begins with a president, desperate to deflect attention from the collapse of his foreign policy, retreating to his one safe zone — ad hominem attacks on critics, this time for lack of compassion toward Syrian widows and orphans.

This, without a glimmer of acknowledgment of his own responsibility for these unfortunate souls becoming widowed and orphaned, displaced and homeless, in the first place. A quarter-million deaths ago, when Bashar al-Assad began making war on his own people, he unleashed his air force and helicopters. They dropped high explosives, nail-filled barrel bombs and even chemical weapons on helpless civilians. President Obama lifted not a finger.

In the earliest days, we could have stopped the slaughter: cratered Assad’s airfields, taken out his planes, grounded his helicopters and created a nationwide no-fly zone. (We successfully maintained one over Kurdistan for 12 years between 1991 and 2003.)

At the time, Assad was teetering. His national security headquarters had been penetrated and bombed. High-level aides were defecting. Military officers were forming a Free Syrian Army.

Against the advice of his top civilian and military aides, Obama refused to intervene. The widows and orphans he now so ostentatiously champions are the product of his coldhearted refusal to do anything that might sully his peacemaking image.

Obama has also charged the Republicans with cowardice, afraid to grant admittance to “3-year-old orphans.” He gave zero credit to the very real concern of governors and other officials that terrorists could be embedded amid the refugees. This is no theoretical proposition. At least one of the Paris attackers came to France by way of Greece.

Obama’s own officials have admitted that the absence of thorough data makes it nearly impossible to properly vet Syrian refugees. In response, many Republicans (and some Democrats) called for a pause in admitting Syrians until alternate vetting procedures are developed. In my view, it would have been better to differentiate among the refugees: Admit women, children and the elderly under the current procedures, while subjecting young men of fighting age to a new regime of far stricter scrutiny.

The concerns of GOP officials were quite reasonable. But there was no need for the Republican candidates to allow the Syria debate to be derailed into a cul-de-sac on immigration — as if the essence of the Middle East issue is a relatively small number of potential refugees rather than the abject failure of Obama’s policies.

Terror is rising around the world — Sinai, Beirut, Mali, Paris. Brussels was shut down by fear itself. The president, in denial about the collapse of his Syria policy, denounced those demanding a change in course. His secretary of state actually acknowledged a rationale (if not legitimacy) for the machine-gunning of a room full of Charlie Hebdo cartoonists for offending Muslim sensibilities with a drawing.

Beyond that is the strategic surrender of the Middle East, for 40 years dominated by the United States, to Russia and Iran, who now dictate the terms. Which is why, for example, we dare not impose a protective no-fly zone. It’s too dangerous. Russia has filled the Obama vacuum.

Facing a massive failure of seven years of Democratic foreign policy stewardship, the GOP candidates have instead tried to outbid each other in being tough on Syrian refugees. This descent into xenophobia was led, as usual, by Donald Trump. Amid bushels of word salad, he concurred with registering American Muslims, raised alarms about Arab-American treachery (“thousands and thousands” on TV cheering the World Trade Center collapse) and promised not only to deny entry to Syrian refugees, but to send back the ones already here.

Can you see it? Packing them onto his 757, the one with gold-plated seatbelts, then dumping them — orphans, widows, the lot — into a war zone to await the next regime barrel bomb.

Other GOP candidates have issued Trumpian echoes. The Muslim registry had no takers. But some have advocated shutting out all the refugees or taking Christians only. They are chasing the polls showing strong anti-refugee sentiment.

How deeply shortsighted. It may work in the GOP primaries. But Trump-like anti-immigrant, anti-foreigner, now anti-Muslim, anti-Arab rhetoric — and don’t forget those cunning Chinese stealing our jobs and ruthless Mexicans raping our women — will not play well in a general election.

Politically, it will be fatal. John Kasich has forcefully denounced this slide into the swamp. Where are the others?

Charles Krauthammer’s email address is letters@charleskrauthammer.com.

Copyright 2015, The Washington Post Writers Group