Take note of some of the things we can be sure were sloshing around in U.S. President Donald Trump's head last week while he was also making his momentous decisions about Iran: his impeachment, his Senate trial, the November election.

If you think it's possible none of that was on his mind, check his Twitter account. It's all there. He's an open book.

Trump admitted years ago that he saw war with Iran as a clever ploy to distract attention from a faltering presidency in an election year. At the time he was speculating that's what Barack Obama would have to do to win in 2012. His analysis is preserved for us on video.

Trump was, of course, wrong. Obama won re-election handily without making war on Iran. Now it's Trump's turn: his re-election prospects are uncertain; Iran is in the crosshairs. Is he, as he's boasted before, "cocked and loaded"?

Of course, we can't ever be sure about his motives or anyone else's. We will likely never know everything that led the president to decide to escalate the Iran situation. But as the world waits nervously to see whether the U.S. stumbles into another Middle East war, it's possible to understand how we got to this point even if we aren't exactly sure why we're here now.

The Iran strategy until now

The Trump administration's Iran strategy was straightforward — ignore the advice of most of America's allies and unilaterally:

Break the 2015 nuclear deal agreed between Iran and the leaders of the world's great powers, most notably Obama (even though Iran has been in compliance with the deal's terms);

Apply "maximum pressure" on Iran, mainly by restoring the economic sanctions that had been lifted under the Iran deal, so as to;

Force the Iranian regime into a corner of "increasingly difficult choices" and thereby;

Compel the regime to return to the negotiating table and accept a new and stricter nuclear agreement dictated by Trump.

Occasionally, Trump has behaved as though provoking the overthrow of the Iranian regime was his real intent. But officially, the goal remained to get a deal curbing Iran's nuclear program that Trump could tout as a better deal than the one Obama got.

U.S. troops wait before they head out for a deployment to the Middle East on Saturday, in Fort Bragg, North Carolina. Soldiers from the Immediate Response Force of the 82nd are part of the approximately 3,000 troops being deployed as tensions increase with Iran in the region after a U.S. airstrike killed Soleimani. (Andrew Craft/Getty Images)

So far, it has not worked. Rather than capitulate to the Trump strategy, Iran applied its own form of "maximum pressure," including repeatedly attacking oil tankers near the Strait of Hormuz and shooting down a U.S. drone.

Soon after that drone went down last June, Trump ordered a retaliatory airstrike. Then, 10 minutes before launch, he abruptly cancelled it. He said he'd just found out the strike could kill as many as 150 people. He wasn't soft-hearted; he just felt the response was disproportionate to the offence. Or so he said.

A dark corner for Trump

But to Iranian leaders it might have looked as though Trump had simply lost his nerve. Maybe they felt emboldened. In any event, they continued with provocations leading up to the events in Iraq that roused Trump to respond last week with the order to kill Maj.-Gen. Qassem Soleimani — a move many analysts have criticized as massively disproportionate.

For decades, Soleimani had been Iran's pre-eminent mastermind behind plots that killed enemy combatants and innocents alike. His exalted stature in the Iranian regime means that the avenging of his death could result in a lot of spilled blood — maybe American blood. How Trump will react to that raises the possibility that the president has now recklessly backed himself into a dark corner of "increasingly difficult choices."

It was a given that after Trump had him blown up, even Trump's harshest critics would grant that the Iranian general had it coming. But the issue is not whether the strike was warranted, but whether it was wise. Was there suddenly a compelling new reason to take out Soleimani that hadn't already existed for years, decades even? After all, both Obama and President George W. Bush reportedly passed up opportunities to kill Soleimani, believing it could provoke a destabilizing reaction that the U.S. would not be able to control. What changed?

Gen. Qassem Soleimani, head of Iran's elite Quds military force, was killed early last Friday morning, along with officials with Iran-backed militias, in a drone strike on their two-car convoy that was leaving Baghdad International Airport. Trump said the general 'was plotting imminent and sinister attacks on American diplomats and military personnel.' (Mehdi Ghasemi/ISNA/AFP/Getty Images)

Initially last week there were a few sensational reports that Soleimani was planning an imminent coup against Iraq. Something like that could explain the U.S. response.

But then the Trump administration made unspecified claims that Soleimani was making plans for imminent attacks on Americans. In that case, why take out the planner and not deal with the attackers?

The overriding message from Trump and his team was that Soleimani was a bad guy and the world's now better off. Virtually everything else they brushed off with some version of "trust us, we know what we're doing" reassurance.

But it's important to note not even Iraq is buying that message. Yesterday the Iraqi parliament voted to expel all foreign troops from its soil at some unspecified time. A clear rejection of Trump's tactics at a critical time, and a decision that would be welcomed in Tehran.

And that gets to the heart of the problem.

On the first full day of Trump's presidency, when Sean Spicer used his television debut as press secretary to lie about the size of Trump's inauguration crowd, wiser heads warned of a day when the handling of something important like national security — or even war — might depend on the trust and credibility of the president and his team.

If things head sideways with Iran, as it appears they might, and there's American blood involved, that time will have come.