So, I'll try to be brief, but I'll mention, in passing, yet another (the fourth) attempted assassination on Trump and/or members of his administration by a leftie.
The party of no guns and protecting Democracy certainly has a strange way of demonstrating their resolve.
Some, imprecision, is inevitable, so I hope that the point will be taken, rather than nit-picked.
Over the last quarter century or so, since the fall of The Wall the US Strategic perspective has shifted more than once. The apparent end of near peer competition caused a move to oppose asymmetric warfare rather than the battles envisaged on the plains of Northern Europe, and resulted in the substantial reduction in naval forces, the downgrading of the B1 bomber, the establishment of strategic arms limitation, and the reduction in the builds of the F22 and B2.
Around the turn of this century the US was starting, somewhat reluctantly perhaps, to encourage the development of an EU based European "army" with Blair and the UK in the lead, and had started reducing the resources spent on Defense (War?) (Where did the European army go? All talk, no action).
https://www.iss.europa.eu/sites/default/files/EUISSFiles/cp039e.pdf#:~:text=During the intervening years, it,States provided most of the
During this time China was perceived as being on the road to liberalization- courtesy of the rules of Jiang Zemin and Hu Jintao- and economic cooperation etc. was the big thing. The theory being that once liberalization and capitalism were entrenched that the installation of Western style Liberal democracy would naturally take its course, just as it was doing in the old Soviet Union.

The events of 9/11, with the clear superiority of Western (i.e. mostly American) weaponry etc. being demonstrated, allowed complacency to set in.
Well, that didn't account for Putin and Xi. The strategic needs shifted, a pair of near peer adversaries started to develop, and the US establishment, not to mention the Europeans, just refused to acknowledge the shift. The US had pared back their Defense spending to about 3.5% of GDP from 6.5%, and the Europeans mostly down to sub 2%, and as low as 1.2% (Spain, I'm looking at you) while offering lip service to Nato. Defense assessments did declare that the US would not be able to guarantee successful engagement in two or more theaters with near peer adversaries, but nothing seemed to be done. The Europeans/Canadians were actively encouraged to re-arm, but they did nothing but provide more lip service, transfer more money from defense to social services, and increasingly put in place mechanisms to obfuscate and deny the social fracturing that was taking place due to their immigration policies.
During this time Nato got involved in Serbia and Libya, neither of which were defensive actions, using force to impose political goals- including the bombing of civilian infrastructure (power generation, bridges etc.) and the indirect killing of opponent leadership. The US Presidents in these cases were Democratic (Clinton, Obama).
The Europeans embraced the Climate religion, while ignoring/miss representing many IPCC conclusions, and decided to not use their own resources but rely on an increasingly expansionist/belligerent Russia and an increasingly more insecure Persian Gulf (Iran has repeatedly threatened to shut down the Strait of Hormuz since the revolution) to supply their fossil fuel needs.
Germany went full idiot by shutting down their nuclear plants as an apparent reaction to the Fukushima Tsunami.
In came Trump. The encouragement became- more. He started to demand that non-US Nato members should actually live up to the treaty goals for expenditure.
The Europeans chose a passive aggressive approach, like pouty children, while refusing to give up their social support framework and were increasingly relying on the import of mostly third world "workers" in the hope to maintain their population.
So here we are, 2026. A Republican president sees the obvious.
Iran, who has been promising Death to America and Israel since the Islamic revolution 47 years ago (well done France!) has just boasted in "negotiations" with the US of their stock of 450kg or so of 60% refined U235 - enough for 10 or 11 bombs, by their own admission. This level of purification even as it is, could be used to produce gun style weapons of low yield, but Israel (again by Iranian admission) is a one bomb country, and the bomb need not be loaded on a missile to be effective. Heck, it could even be loaded onto a ship and parked off New York (not necessarily a bad thing) for example and detonated as a threat to the US.
The long in place Ayatollah Fatwa that has been cited as a certainty that Iran would not develop nuclear weapons can, effectively, be negated at any time. It does not have the power of law, even in a Theocracy.
Israel, purportedly, has between 60 and 200 nuclear weapons. They have 6 Dolphin submarines which have been configured to allow up to 16 submarine launched cruise missiles each with nuclear tipped cruise missiles, reportedly with a 1500km range. They will likely retaliate if a nuclear attack occurs. The Iranians care nothing for the temporal state of their population, or that of their neighbors in Pakistan etc. who would necessarily be badly affected by an Israel/Iran nuclear exchange.
Iran has been steadily extending their ballistic missile range- and despite their statements to the contrary there was reason to believe that the goal was to exceed the 2000km range that they said was their limit (subsequently demonstrated by the attack on Diego Garcia), but to include the bulk of The West (Europe, including the UK) and eventually the US. There are also reports that they have been doing design work on miniaturized warheads capable of being loaded onto an ICBM. They are also working on Pickaxe Mountain as a way to make their nuclear capability impervious to non-nuclear assault.
Does this constitute an imminent threat? Personally, if someone says, repeatedly, that their goal is to kill you and that they think God will reward them in Heaven if they do, then I take it seriously. I don't see the need for the weapon to be lodged in my throat before it becomes imminent. The Trump admin apparently sees it this way too. This leads to Trump being willing to do what his predecessors knew would someday be necessary but were unwilling to do.
So, here we were. The decision to attack Iran and take out its leadership/capabilities had been taken.
What about the Europeans, does the US involve them?
Let's assume the US did. What would happen. Well, who do they tell, the UK, France, Germany? How about Poland or Italy, or Hungary or Spain?
How many of them would be willing to help? How many would try to stop it? How many would actually inform, either directly or indirectly, the Iranians?
How long would such conversations take?
The economic consequences to much of Europe would be severe if the Strait was closed due to their idiotic prior choices, and that was always going to be a possibility.
Europe had already made decisions that would make the political choice to assist very non-palatable (Oil, restive Muslim populations), for many of their countries, and, frankly, their ability to actually help, besides allowing the US to use US bases on their lands, was almost non-existent. So, rather than openly admitting that this was a necessary thing, they crossed their arms, pouted, said no, you can't use your bases, etc. etc.
I do agree that the Trump admin could have been a little more diplomatic, but I'm not surprised that they were not. I probably would not have been if I were in charge.