Why 3-bet pre though given we are oop and can pretty well define MP2's range to be more than likely ahead of us?

If we 3-bet and he calls then calls down an A flop do we just shut down and let them take control?

I don't have a problem with my play while MP2 was in the hand, my question was if my reasoning for thinking BB was squeezing was correct, but could also add in what to do if MP2 reraises him, do we fold? (in my mind the answer would be yes)