Not everyone and not necessarily.  Sometimes during times of war, investors start buying up defense stocks and related ones.

In any case, I'm not even up to speed on what's going on in Iran at the moment and I only heard about Trump ordering a hit on someone over there by reading a thread on bitcointalk.  That's sad--I've got to pull up a news site after I write this post.  But as far as bitcoin is concerned, I don't think war is going to affect its price all that much unless it's an all-out world war, and I don't think that's going to happen because of a situation with Iran.  It's not like the US and Iran have ever been that friendly, and we almost attacked Syria a few years ago under the Obama administration.  That was after bitcoin was created and it didn't seem to have much of an effect.

But we'll see.  And I'm hoping Trump doesn't do anything even more stupid before he gets kicked out of office.