"What exactly are folks afraid of?"

As you say, Strick, America has tended to keep the heavy-handed stuff for places that it has decided are within its sphere of influence. However it seems very posssible, to say the least, that with modern speed of communication and so forth that sphere of influence, which it sees iitself as needing to control for its own safteyty is going to be a great deal larger, to include places of strategic importance for raw materials, and places which could conceivably imply a threat.

And that historically is how extended empires have grown - not so much through calculated expansionism (leaving aside cases like the USA expanding across America, or Russia expanding across Asia), but rather through a need to extend "defensively". Defending trade routes, preemptive attacks on potential enemies, establishing secure forward bases and so forth.

And unfortunately that "Project for a New American Cenbtury" was not a forgery, and the people who are most closely associated with it appear to be in the driving seat.