A suspected poison gas attack by the Syrian regime on the rebel-held town of Khan Sheikhoun has killed at least 74 people — including 16 women and 23 children — and wounded over 350, according to the Syrian American Medical Society. Videos and photos taken by activists and medics on the scene showed victims choking and fainting, some with foam coming out of their mouths. These videos and photos have not been independently verified.

A few hours later, Syrian warplanes launched another airstrike on one of the medical clinics where victims of the first attack were being treated, the New York Times reports. Let that sink in for a moment: Bashar al-Assad gassed his own people, then bombed those desperately trying to save the lives of those suffering and dying from the chemicals.

The European Union and President Recep Tayyip Erdoǧan of Turkey have condemned the attack and blamed the Syrian government. European Union diplomatic chief Federica Mogherini said the Assad regime bears "primary responsibility" for the attack. France has called for an emergency meeting of the United Nations Security Council, and the UN office responsible for chemical weapons is reportedly investigating the attack.

The White House condemned the attack as "heinous" and "reprehensible" and blamed the Obama administration for failing to be tougher on Assad.

"These heinous actions by the Bashar Assad regime are a consequence of the past administration’s weakness and irresolution," press secretary Sean Spicer said. "President Obama said in 2012 that he would establish a ‘red line’ against the use of chemical weapons and then did nothing."

Rep. Eliot Engel, ranking member of the House Committee on Foreign Affairs, issued a statement saying he was "horrified by the Assad regime's attack," and accused the Trump administration of emboldening Assad:

Sadly, the Assad regime is likely feeling empowered right now. This week, the Trump Administration moved toward appeasing the butcher in Damascus and accepting how Moscow and Tehran have enabled and protected him. Now that Donald Trump has put the world's superpower firmly on the sidelines, I fear what may come next for the Syrian people.

Speaking last week at the Council on Foreign Relations, US Ambassador to the UN Nikki Haley signaled that the Trump administration is backing away from the Obama administration’s stated policy of demanding that Assad step down as part of any final deal to end the country’s brutal civil war.

"I’m not going to go back into, ‘should Assad be in or out?’" Haley said. "Been there, done that, right?"

That’s less of a shift than it appears to be on the surface, given that the Obama administration failed to bolster its tough talk about Assad with any serious efforts to oust him. The former president failed to use force after Assad violated Obama’s self-declared "red line" and mounted a chemical attack near Damascus that killed roughly 1,000 people in 2013.

Obama also personally vetoed the advice of his entire national security team in 2012 and opted not to arm the moderate Syrian rebels when they were scoring significant battlefield wins against Assad.

Still, there’s no doubt that Trump is even less committed to Assad’s ouster than Obama was. The president has a well-known soft spot for autocrats willing to hammer Islamist militants (resulting civilian casualties be damned) and has repeatedly expressed a desire to work more closely with Russia.

That matters because Russian President Vladimir Putin is Assad’s strongest foreign ally and has sent troops, weaponry, and money to help Assad battle the rebels working to unseat him. With the Kremlin’s help, Assad has been steadily reclaiming lost territory from the insurgents, including the onetime rebel stronghold in the city of Aleppo.

The Syrian regime flatly denies accusations that it was involved in today’s chemical weapons attack. In an interview with the BBC, Syrian member of parliament Fares Shehabi called the accusations "nonsense" and "fake news." He insisted that the Syrian government did not have chemical weapons and had no reason to use them even if they did, and suggested instead that perhaps a chemical weapons depot controlled by the al-Qaeda militants in the area may have exploded.

"I clearly deny that neither the Syrian army nor the Russian army used any chemical weapons in Syria. Of course I deny," said Shehabi. "And this is proven by the UN. There was a committee by the UN that double-checked on this and clarified that we don’t have any chemical weapons."

"We are not going to take any of these allegations seriously. We will laugh at it," he added.

(The Russian defense ministry has also denied carrying out airstrikes in that area today, according to the BBC.)

Take the Syrian denials with a shaker of salt, for a simple reason: This isn’t the first time the regime has been accused of using chemical weapons on civilians, or of deliberately bombing hospitals and medical clinics.

The Syrian regime has used chemical weapons before

Nearly 1,500 civilians were killed in chemical weapons attacks in Syria between the onset of the civil war and 2015, according to a March 2016 report by the Syrian American Medical Society.

The report documented 161 chemical attacks in Syria, details of which were gathered from doctors operating on the ground in the areas that bore the brunt of chemical warfare. In addition to the fatalities, the report found that the chemical weapons wounded another 14,581 people.

This most recent attack in Khan Sheikhoun is the deadliest chemical attack in Syria since sarin gas killed hundreds — maybe even as many as 1,000 — of civilians in eastern Ghouta, near the capital of Damascus, in August 2013. Western countries blamed the Syrian government for the attack; the Syrian government blamed the rebels.

That was almost exactly one year after Obama warned that he was prepared to bomb Assad if he used chemical weapons, only to back away at the last minute in what many allies saw as a key abdication of US credibility in the region.

There are no good guys in the Syrian civil war, and both rebels and Syrian regime forces have been implicated in chemical weapons attacks. In August 2016, a year-long joint inquiry by the UN and the Organization for the Prohibition of Chemical Weapons (OPCW) into the use of chemical weapons in the Syrian war reported that in at least two cases, they had found "sufficient information to determine that the Syrian Armed Forces were responsible for the attack which released toxic substances." In another case, they named ISIS as the culprits.

Attacks on medical facilities have also been a central feature in the war in Syria. There were 382 such strikes between March 2011, when the Syrian civil war began, and June 2016, according to data collected by Physicians for Human Rights.

The vast, vast majority of those attacks — 90 percent, to be exact — were conducted by Syrian government forces or by Russian forces fighting on behalf of Assad. These forces have also killed more than 700 medical personnel in Syria, according to the group’s statistics.

A UN independent inquiry commission on Syria stated in a September 2016 report that "[t]he pattern of attacks [by the Syrian regime], and in particular the repeated bombardments, strongly suggests that there has been deliberate and systematic targeting of hospitals and other medical facilities during this reporting period."

In other words, this latest chemical attack, and the follow-up attack on the medical clinic treating victims, is a gruesome and unspeakable atrocity — but it’s nothing new. It’s merely a common feature in one of the most brutal wars the 21st century has seen, one that shows no signs of ending anytime soon.