The U.S. tends not to invade countries in which U.S. corporations are doing business. In fact, that tends to be the purpose of many U.S. wars: to get U.S. corporations into the conquered country. See the book The Secret History of the American Empire: The Truth About Economic Hit Men, Jackals, and How to Change the World for lots of details.
The liberal / conservative paradigm is now a false one. Conservatism has changed. Conservatives are generally not Jeffersonians who believe in a limited federal government. They are Hamiltonians who believe in a strong federal government. Mitt Romney is a prime example of this. They want to expand the federal government through endless warfare.
The true conservatives are now libertarians.