An intriguing forecast, but just a hypothetical scenario at best. It's an open secret that Pakistan military has been in on this from day one. All the public statements calling for Americans to leave Pakistan, are just a part of an elaborate charade of deceiving the nation.
Look, first of all, we need to define the 'rules of the game'.
Does Pakistan have a 'democratically elected government? Yes. I care not whether you like it or not, or whether you want Shariah law, the point is that we have a democratically elected government.
Now that is cleared up, technically, who is responsible for foreign policy and 'evicting the US (or anyone else) from Pakistan? The GoP, not the Army, not the PAF.
By blaming the Army/Military, you are basically serving Zardari and his corrupt lackeys. They WANT to project the image that the 'Army is making us do this' despite the fact that Wikileaks and the firing of former FM Qureshi makes clear that they have no intention of taking on the Yanks. The decision to 'kick out the US, shoot down the drones, kick out all but essential US diplomatic officials' needs to be taken by parliament, officially, with both opposition and government in support of such a position.
The reason for parliament taking these decisions is that once Pakistan does assert itself against the US, expect all economic US aid to end, IMF assistance to end, and possible also expect US trade and other sanctions. Now, personally I believe that Pakistan has the resources to overcome this, if managed properly, but our politicians have no ability to take tough decisions, and therefore are highly unlikely to take decisions that will make the economy tank (for a while at least) and therefore lose their seats in elections.
Were the Army to take this decision unilaterally, all these politicians and the media would be ranting and blaming the 'dictator Army' for usurping civilian power and destroying the economy and the country.
Do you understand now why this 'change in policies towards the US' needs to come from Parliament, not the military? Given the potential consequences, parliament, as representative of all Pakistanis, needs to take a unified stance, explain what they plan to do, what the consequences are, what Pakistanis can expect will happen, and then act.
Don't make the Military a scapegoat here.