But none of this is new, what's new (aside from the anthropogenic cause) is that Homo sapiens' usual coping mechanism of migration is no longer feasible.
This is where the problems and conflicts will come.
Migration is extremely common, that most migrants do not reach Europe or the USA did not mean that they are not migrating.
I may assume that you mean that Europe/USA cannot be the destination of all of them. But, I do not even think that most people is so willing to change to a different place. They will migrate as much as needed but not more.
If Iran's anything like Europe (and I truly have no idea if it is) then the real heat won't hit until July.