Your second paragraph is answered by post-9/11 American foreign policy in Iraq (to say the least). But just to echo that answer, yes - Halliburton (and plenty of other private military, security, cyber security service companies) did and continues to thrive off war profiteering. War is an economy. That's why the military-industrial complex is discussed so frequently. Not many other nations subsidize an entire market segment to the tune of hundreds of billions of dollars a year. One that, again, generates profit off of the selling of weapons and arms to be used against other human beings.