The Saturday attack on Saudi oil facilities, which took 5.7 million barrels of oil per day offline, is the escalation that wasn’t supposed to happen. Now that it has happened, we enter perilous new terrain.

America has blamed Iran and hinted at some sort of retaliation. Iran has denied responsibility, while the Houthis gladly take it. There are conflicting reports of where the missiles or drones were launched from, which we will learn more about in the coming days.

In the meantime, Trump is in a tight spot of his own making, with neither escalation nor retrenchment looking to be attractive options.

It is still uncertain when Saudi Aramco can get everything back on line. The attack showed sophistication. Critical nodes were hit. If the facilities are quickly repaired, that lessens the gravity of this event. The Iran-Iraq War in the 1980s showed the resiliency of oil installations, as Iraqi bombers pounded Kharg Island, where Iran exported much of its oil, yet the Iranians managed to keep the exports flowing. This suggests that a war of attrition today would be possible without major disruptions, though the impact of new technologies of attack and resistance makes any guess hazardous.

If past crises are any indication, a sustained loss of 5.7 million barrels per day, over five percent of world oil consumption, would likely quadruple oil prices. Strategic petroleum reserves can cover this to a certain extent: the U.S. system can pump 4.4 million barrels per day. But it would exhaust its reserves in 150 days at that pace. We do not know whether more strikes will be forthcoming or whether such efforts can be successfully suppressed with airpower or invigorated defenses. All we can say is that the great game has advanced to a new stage.

From the beginning, escalation has seemed the likely consequence of the Trump administration’s decision to asphyxiate the Iranian regime by cutting off its ability to export oil. This was a declaration of economic war. That is the polite term, as it is an action every international lawyer on the planet, back in the day when these things mattered, would have called an act of war without any precious qualifiers.

It turns out that there may be some street cred to Iranian President Hassan Rouhani’s assertion that if Iran isn’t allowed to export oil, others will face obstacles too. Tit for tat. Got a quid? Here’s a quo. The funny thing is that any significant threat to Saudi capacity creates a pressing need to get Iran’s spare capacity onto the world market. As to which side now has more leverage, in a position to squeeze harder, that’s a tough question. Putting it nicely, the Iranians can, if their will is stout, impose huge costs on the United States and the world economy. They would only consider that if pressed extremely hard, yet the United States has been pressing them extremely hard for over a year now.

Remember that the purpose of America’s economic war on Iran was to force Iran to submit to 12 demands issued by Pharaoh Mike Pompeo in his edict delivered on May 21, 2018. It was really disappointing that Pompeo didn’t raise the obvious thirteenth demand and insist that the embargo would not be lifted until an American regent was appointed in Tehran, taking the Islamic Revolution under neoliberal guidance until circumstances changed, after which Iranian democracy would be restored to its former lack of glory. That was implied, to be sure, but we didn’t get much straight talk from Mr. Pompeo on that point.

This ultimatum was reminiscent of the demands that the Austro-Hungarians made on the Serbs on a certain date in 1914. Make them as extreme as you can, said the inspired diplomatists looking for war. World reaction was then unfavorable. Winston Churchill, in charge of Britain’s navy, called it “the most insolent document of its kind ever devised.” The resemblance to Pompeo’s ultimatums hardly shows the imminence of a 1914-like crisis today, but there is a certain arrogance to both the U.S. warmongers and Austro-Hungarians. The Austrians got the war they were looking for; the neocons may yet get theirs.

Trump’s renunciation of the Iran nuclear deal is mostly about Israel and its perceived security requirements. Not only must Iran not have a single nuclear weapon, it must not have the theoretical capability to produce a weapon, were the Iranians to break from their pledges under the Non-Proliferation Treaty and the JCPOA. This imposes a requirement on the Islamic Republic that no other medium-sized power has had to endure. That the Iranians are bearers of an ancient civilization makes the humiliation all the more painful. Those 12 demands were not designed to produce a settlement; they were designed to produce a crisis, as they now have done. Regime change lies back of them—that or simply the immiseration of another Muslim country.

American policy toward Saudi Arabia, on the other hand, has recently been mostly about arms sales. People say all the time that the oil companies are the heavyweights in this drama. In fact, they are secondary. What has driven events in the recent past is the military-industrial complex salivating over the sales of high-priced and high-tech U.S. armaments to sheikdoms with money to burn. The MIC plunderers, like the Hollywood moguls, understand that you simply must have the foreign market to make the big profits. Politicians see such sales as a way of making our own arms purchases remotely affordable and thereby politically palatable. For these reasons, foreign arms sales to reprehensible characters is Washington’s go-to move, a win-win for the plutocrats and the praetorians.

The United States acted under no prompting of national interest in so aiding and abetting the Saudi war in Yemen, but its hankering after all those lucrative contracts was just too much temptation. When the flesh is weak, as it seems to be in Washington, burning flesh is not a problem. Trump saw it as a great business deal and had no compunctions about the human fallout in Yemen. The Democrats—a certain Democrat, especially—did what was once said of Austrian Queen Maria Theresa after the Partition of Poland in 1772: “She wept, but she took.”

The president may have outsmarted himself this time. He got rid of National Security Adviser John Bolton because he didn’t like Bolton’s across-the-board hawkish recommendations, but he signed on to the very big change in U.S. policy towards Iran that Bolton had recommended. Trump thought he was in control of the escalation. But when you declare your intention to asphyxiate another country, you’ve committed an act of war. Retaliation from the other side usually follows in some form or fashion. You can then advance to your ruin or retreat in ignominy.

Trump has threatened retaliation, but he surely does not want a big war with Iran. His supporters definitely do not want a war with Iran. Americans in general are opposed to a war with Iran. Mysteriously, however, the U.S. declaration of war on Iran in fact—though not, of course, in name, heaven forbid—escaped notice by the commentariat this past year. The swamp’s seismograph doesn’t record a reading when we violate the rules, but when the other guy does, it’s 7.8 on the Richter Scale.

The whole drama, in a nutshell, is just the old-fashioned hubris of the imperial power, issuing its edicts, and genuinely surprised when it encounters resistance, even though such resistance confirms for the wunderkinds their view of the enemy’s malevolence.

Is Trump trapped? That is the question of the hour. He faces strong pressure to do something in retaliation, but that something may aggravate the oil shock and imperil his re-election. As he dwells on that possibility, he will probably look for ways to back down. He will try to get out of the trap set by the U.S. economic war on Iran without abandoning the economic war on Iran. But that probably won’t work; that was Iran’s message over the weekend. Were he to abandon the economic war, however, he would get a ton of flak from both sides of the aisle in Congress. The commentators would scream “appeasement!” In Washington lobby-land, we’d be back to 1938 in a flash.

Does the president have the gumption to resist that tired line? I hope so.

David Hendrickson teaches history at Colorado College and is the author of Republic in Peril: American Empire and the Liberal Tradition.