My 2 cents...
Except for Afghanistan, I don't think Pakistan has much of a value through is location of being a "strategic one".
The Americans don't need Pakistan to get to Iran, they already have a naval military base in middle east to deal with Iran, to deal with Russia, the Americans have placed nuclear weapons all over Europe and turkey and to deal with china, they are now forming pacts with India and opening new bases while giving more powerful weapons to their allies in Japan and Korea.
The Americans have a very powerful armed forces that doesn't need any country's strategic location to rely upon...
In my view, the military aid to Pakistan is to limit India. The Americans very well know the bastardized behaviors of Pakistanis. The statements by various CIA and politicians from time to time tells us that the Americans widely know the pakistani behaviors very well. By this, I don't agree with the statement "Pakistanis are milking Americans"...
The rise of china was the biggest mistake of US in 21st century, of course, the Americans couldn't have done anything to stop the rise of china and it was already a UNSC member. All the historical powers around the world have now accepted that the rise of china was a given. And it has risen to its natural state. The question is of India.
The rise of china has has forced Americans to spend hundreds of billions of dollars in military alliances, weapons, exercise and even politically. The new alliance called "P2" states (china and US), is just what it is...both Americans and Chinese recognize that they cannot win against each other and are now making a pact. That is, accept each other as the world power.....and STOP the scenario of P3 states from ever happening!!. Seemingly, even Russians are making a move to kill this P2 alliance.
India is one of the potential candidate of the yet to be born "P3" alliance..........but it is far more clear now that neither the Chinese nor the Americans can afford the rise of another world power.
Billions of dollars of aid to Pakistan through IMF, foreign military sales and economic aid package is to keep Pakistan as counter weight to India. It's a plot to keep India hinged to the regional level than to let it rise to a global level. And the Chinese are making the exact same thing, wherever we go, they tie us with Pakistanis. Wherever we try to become a member (NSG), they tie the membership of India to Pakistanis all the while knowing very well that India now stands in whole different league compared to Pakistanis.