External factor should not be allowed to dictate Pakistan's internal affairs. I don't remember USA imposing any such sanctions against Pakistan due to martial law..please prove me wrong...as uncle sam and the rest of the world is interested in working with the state of Pakistan and they already know who is in the power and visit GHQ more frequently than PM secretariat.
If you treat army as a party, it has 95% approval and no one will be out against PA. PMLn lions normally turn into dogs with tails in between their legs and they run amuck. PPP has no street power and their corrupt leadership is only hiding in UAE. PTI may issue a statement or two but no chance they will take to the streets since no one will join them and it will be more harmful to their politics than beneficial.
But more importantly, in all previous martial laws, there has never been a mass protest and especially the ones involving ouster of the grossly unpopular NS; rather sweets have been distributed on the roads of Lahore. The qeema naan voters of PMLn are not there to take beating by army and police.