U.S. President Donald Trump has managed to maneuver himself into a position that makes a long war on Iran all but inevitable.

About two days ago I was still betting on Trump to chicken out of a war with Iran. The military buildup in the Middle East was insufficient but for a short in-out air campaign on Iran with no discernible value.

But over the last days the U.S. military has sent many more air refueling tankers, dozens of more fighter planes and – most importantly – command and control elements to the Middle East. The force is sufficient for a large air campaign that could be sustained for at least two weeks. An additional carrier strike force has entered the Mediterranean and will be positioned west of Israel by the end of the week. A second carrier strike group is deployed in the Arabian Sea.

Deploying such a large force is extremely costly. Pressure will increase quickly to use it or to stand down.

The last negotiations between The U.S. and Iran went well but ended without any results. Iran promised to come back in maybe two week with a detailed plan on how to proceed:

“We were able to reach a general agreement on a set of guiding principles, based on which we will proceed from now on, and move toward drafting a potential agreement,” Iranian Foreign Minister Abbas Araghchi told state TV after talks with US Special Envoy Steve Witkoff in Geneva.

The two sides will each draft and exchange texts for a deal before setting a date for a third round of talks, he said, cautioning that the next stage would be “more difficult and detailed.”

Two weeks is a long time and the military clock is now ticking faster than the diplomatic one.

The U.S. military is reported to have told Trump that it will be ready to strike by this weekend:

Top national security officials have told President Trump the military is ready for potential strikes on Iran as soon as Saturday, but the timeline for any action is likely to extend beyond this weekend, sources familiar with the discussions told CBS News.

Mr. Trump has not yet made a final decision about whether to strike, said the officials, who spoke under condition of anonymity to discuss sensitive national matters.

With the forces deployed and ready to strike Trump is no longer in a position to avoid a war if Israel wants one. If Netanyahoo were to strike Iran the U.S. would immediately have to intervene to lower the consequences of Iran’s inevitable retaliation.

The deployment of refueling tankers in the Middle East points to the necessity for the U.S. to avoid stationing planes within the reach of Iran’s short range missile forces. Fighters and bombers will have launch from further away, tank up, run their turn on Iran, tank up again and land to reload. The number of sorties that can generated by this will be only half of what a ‘normal’ air campaign would look like.

Any attack will likely start with the firing of one or two hundred cruise missiles. They will be followed by stealth bombers which will try to destroy Iranian air defenses. After that is more or less achieved, waves of strike planes will launch missiles from safe distances to strike at Iranian military and civilian command elements as well as infrastructure in Iran.

Iran will retaliate with waves of drones and older missiles. The aim will be to exhaust U.S. missile defenses. During last years 12-day war it took Iran about eight days to achieve that. Thereafter it used newer missiles which were able to hit their targets in Israel will unexpected precision.

Iran will also use its shorter range missiles to destroy any U.S. element, be it on ground, air or sea, that is within its reach. Irregular forces aligned with Iran in Lebanon, Iraq and Yemen may join the campaign.

Iran is expected to be be helped by Chinese and Russian intelligence. During the war in Ukraine the U.S. established the norm that the supply of intelligence to one party of a war is insufficient to make oneself a combatant. Chinese satellite intelligence will allow Iran to have at all times a clear picture of its enemies disposals.

Iran however is undoubtedly the underdog in this fight. It can not win a war against a country that is several thousand miles away from its shores. The damage a sustained U.S. air campaign will cause will be real and very painful. The real threat is not a one off campaign but a constant deterioration of the Iranian state should the U.S. decide to wage a long campaign of attrition against it as it did against Iraq between the two Gulf wars.

The only way to prevent that is for Iran to use the economic power that comes with its control of the Strait of Hormuz. A blockade of the Strait would raise global oil prices to the north of $100 per barrel. With energy prices going through the roof, and the collateral economic damage cause by it, the chance of the Republicans winning the midterms will go down to nil.

It is doubtful though that Trump still cares about that.