Historical analogy: U.S. invading the Philippines, while it initially seemed like a reasonable idea routing the Spanish, America quickly transformed into the next occupier. The brutal oppression and fierce resistance that followed in all likelihood killed, directly and indirectly, as many as 1.000.000 people. This is also relevant since America frequently used the term “insurgents” to denote the opposition to colonization. In fact the word “war” never came up in official pennings. The “Philippine Insurrection” doublespeak made it seem as though the conflict was between rebels and a legitimate government.
http://en.wikipedia.org/wiki/Philippine-American_War
Of course, since then we have come a long way and now rely on “democracy”, economics, constitutional mumbo jumbo and trumped up elections to provide further legitimacy.

Or one could take an example from Nazi Germany, which is unrelated to American history but nonetheless very poignant. Because obviously, Nazi Germany did not occupy Eastern Europe as they also engaged partisans (and slaughtered civilians)?
“Partisans Then, Terrorists Now…”
http://utah.indymedia.org/news/2005/11/12544.php

Clearly, a nation that was founded on the actions of “terrorists” rejecting British rule should not be so quick to judge.