Trump probably likes being restricted on Iran, considering there's an element within the government who's tried to get him involved in a war he doesn't want. Trump knows much of his base is against it as well. Israel and Saudi Arabia can deal with Iran if they want. If Iran does something stupid, it would just put pressure on politicians to give Trump the authorization to go to war. I don't think Iran is that stupid. Trump needs to be wary of the neocons still within our government who would love to create a problem that gives the president more powers to engage in war, that they can then manipulate by creating situations to pressure the president.
There's still a lot of neocon scum that wants permanent war, but it's obviously getting harder for them to manipulate Trump, and the American people overall. You can only use the same tactics for so long before people start recognizing them and becoming suspicious. I don't think the neocons will ever be as successful as they use to be. The average person on the left and right has started identifying and rejecting the establishment more often, and while they still hold a lot of power I don't see them reversing the course they're on. The W and Obama administration are a major reason for the backlash against neocons and the establishment in general. I don't think W or Obama were the major players behind those destructive wars, but regardless they were in charge and hold responsibility in the end. Bill Kristol needs to give up on the neocon ideology, and rejoin the horrible communist/socialist left of Bernie that his family branched off from. Both factions are horrible, and have created some huge blatant problems in different ways that are antisemitic to acknowledge.