While it is hard to predict what the future will being and while the middle east has been a hotbed for conflict since times immemorial it is likely that taking the Theocratic regime in Iran out of the equation is a net-positive when it comes to limiting the amount of conflict in the region. I intentionally do not use the word 'peace' because I do not see peace ever breaking out there given the historical record and the many sources of conflict.
Destabilizing Iran will make another migration crisis in Europe, will divide it politically because of the rise of anti immigrant far right, and finally set up the scene for a big european war for which russia is preparing.
If US hopes to not be involved in it, it will be up for the surprise.
You think migration of refugees will lead to... civil war in Europe? There's a lot of space in Europe – it could accomodate even all 90 million Iranian refugees and not collapse (let us hope Iranian civilians not made into refugees by Trump and Netanyahu).
Colin Powell, is that you? How have you been, man? Have you been keeping in touch with John Yoo? That guy has been on fire lately! btw how'd those things with the Taliban and Saddam work out?