Let me give it a slight twist.
Why, in your opinion, is US after Iran right now? Let me further give it a twist, why do you think that there is high decibel racket against Iran yet exemptions on trade with Iran being given? Trump is, after all, as per his own statement, a deal maker? Could it be that he is trying to wrest concessions from Iran?
Let me hypothesize, why do you think, in spite of rhetoric in favor of Saudis and against Iran, is US not de-stabilizing Iran? I have seen some members from Pakistan here mention about a desire for Sistan-Baluchistan integration. Pakistan would be a willing party, for obvious reasons.
The goal is to stop Iranian influence in the region that is proving destabilizing to the existing arrangements.
ok i go to evening walk on beach no benifit to sit here 
.... besides that pakistan has opted the block of Russia china and it is the right decision, American are losing every where and this is just one more blow to their international dominance they are out of middle east, central asia and now from south asia curtsy to Donald trump