While there aren't any foreign bases on US soil in the strictest sense, there is a foreign military presence on US soil by way of joint operations. As pointed out earlier in this thread, there are joint operations in the country with NORAD (US and Canada) and so on that pretty much make the foreign military operations a part of our own operations. NATO (most of North America and Western Europe) has a lot of the same deal.
Many times, the bases being in use in foreign countries aren't just US only either. The member nations of NATO tend to use all of these installations, we're just the member nation of that organization with the most ability to establish bases. I happen to have friends with family in the Canadian military that make use of American built military bases in European countries since it's easier to pool resources than to construct new bases from scratch. We also hold war games with these friendly nations on each others' soil in rotation. The result is that we often have bases that are not being used just by us but by anyone who is associated with us, including bases here on US soil that, while not strictly a foreign base, are in fact in use by foreign powers.
In fact, one of the cute things about foreign militaries on US soil is that we've gone so far as to let the British use American grounds for testing their nuclear weapons back during the cold war. The Nevada Testing sites were used by the British for MULTIPLE nuclear tests throughout the cold war, some as recent as the mid to late 80s. In fact, there were 9 nuclear tests that I'm aware of from 1983 to 1991 by the UK (for their "Chevaline system") on US soil. That's not just letting them borrow some land, that's letting them blow it up.
So, while we do have a disproportionate number of bases on foreign soil (some of which unwanted by the local populace), it's not entirely unilateral and provides an infrastructure in use by more than just us.
Many times, the bases being in use in foreign countries aren't just US only either. The member nations of NATO tend to use all of these installations, we're just the member nation of that organization with the most ability to establish bases. I happen to have friends with family in the Canadian military that make use of American built military bases in European countries since it's easier to pool resources than to construct new bases from scratch. We also hold war games with these friendly nations on each others' soil in rotation. The result is that we often have bases that are not being used just by us but by anyone who is associated with us, including bases here on US soil that, while not strictly a foreign base, are in fact in use by foreign powers.
In fact, one of the cute things about foreign militaries on US soil is that we've gone so far as to let the British use American grounds for testing their nuclear weapons back during the cold war. The Nevada Testing sites were used by the British for MULTIPLE nuclear tests throughout the cold war, some as recent as the mid to late 80s. In fact, there were 9 nuclear tests that I'm aware of from 1983 to 1991 by the UK (for their "Chevaline system") on US soil. That's not just letting them borrow some land, that's letting them blow it up.
So, while we do have a disproportionate number of bases on foreign soil (some of which unwanted by the local populace), it's not entirely unilateral and provides an infrastructure in use by more than just us.