Obviously I don't have near enough information to have anything like certainty. However, here are some tentative considerations.
In August, 2017, President Trump delivered some remarks regarding his Afghan strategy. One overriding point was this: "We are not nation-building again. We are killing terrorists."
With that in mind, consider Trump's willingness to negotiate with just about anybody, if the negotiations serve US interests and are conducted in good faith. Trump has been attempting to force Iran to the negotiating table through sanctions, but Iran appears to have resisted negotiations in which US interests would be recognized. The Iranian goal is simply to force the US from the Middle East.
While that is attractive outcome for most Americans, for various reasons it seems unlikely to happen. Thus, Trump's assurances to Americans: We're no longer in the business of nation building. Instead, we'll do deals. But if terrorism is employed against the US, we'll respond as we see fit. Proportionality as traditionally conceived may not enter into our response. Preemption is a possibility, both proximately as well as for the extended future.
In this case it appears Trump had grown frustrated with Iranian refusals to negotiate on what Trump regarded as reasonable terms. Instead, Iran appeared to be resorting to a strategy of pin pricks that the US has generally disregarded in the past. Or which might provoke a disproportionate response in traditional terms--as nearly happened with drone downing.
Trump's message, therefore, seems to be one of unpredictability. Don't anyone think they know ahead of provoking the US what the response will be. Count on a response, but don't think you can predict its nature or extent. A strategy of pressure through calculated provocations could be a strategy of playing with fire. In the art of the deal predictability is a weakness.
There are dangers in this for the US, as well. Nothing will be simple. Syria and Libya remain in turmoil. Saudi Arabia has revealed its essential weakness through its Yemen adventure. Turkey is aggressively seeking to expand its influence not only along its land borders in Syria and Iraq--which will inevitably bring it into conflict with Iran--but also throughout the eastern Mediterranean. Russia, of course, has interests it wishes to maintain. Afghanistan, on the eastern side of Iran is a multidimensional mess.
Of course, the one non-Muslim country most worried by all this is almost certainly Russia. Perhaps if Barr/Durham can sufficiently bring the Dem inspired Russia Hoax to a conclusion by exposing it to daylight Trump will be able to do a deal with Russia with regard to the Middle East. Especially with regard to Iran and Turkey.
Trump never told us his presidency would be boring.
An emailer recently sent me a NYPost editorial re Trump's reelection chances--rating them as excellent, despite determined establishment hostility. I remarked, referencing "the current crisis in the Middle East"--or should that be "usual"?--Trump seems not inclined to play it safe leading into the election cycle. Then I added that playing it safe is so often a snare and a delusion, the oppositie of safe. That's something that Trump probably understands as well as any politician alive.
UPDATE: The other day I quoted Don Surber, a shrewd observer of many things, to the effect that invading a country under false pretenses (Iraq, WMD) tends to PO the natives. It's true, and it's something that Americans need to take much more seriously. Trump has repeatedly said he wants to bring the troops home, and I take him at his word. He says he wants to get out of the business of nation building, and I take him at his word on that, too. What could cause him problems going forward after the Soleimani assassination is that, three years into Trump's first term, we still find ourselves in a betwixt and between position, with not that much of Trump's foreign policy for the Middle East implemented.
