Europe has one 'weapon' they can use but they can use it just once: dump the bonds. The problem with that is that you need a reason big enough that by the time you're going to do it it will likely be too late to be effective and as a punitive measure it makes little sense, it's just one step short of a declaration of war. If Trump goes ahead with this madness then tomorrow morning the world economy will be in shambles, no matter what. Note that we got here ostensibly to 'free the Iranian people', apparently they need to be murdered to make them free. It's grotesque.

Trump is a boomer who grow in a age where American power was incontested. Second, he is a narcisist and he will let Rome burn down before he let someone call him a loser.

Third. Even if our gerontocrat had a saner mind, I doubt he would be able to control Israel. Let them alone fighting Iran, with their missile defense depleted leting Iranian missiles rain down everywhere, Bibi would surely nuke Tehran and the Yemen, so I don't even think there's a way out of this.