this isn't exactly a new concept. all throughout the Cold War, the US used operatives in Latin America and Asia to bring about democratic change in certain countries, to "save" them from having a socialist or communist regime. we even supported corrupt bastards like Chiang (RoC/Taiwan) in an effort to prevent the spread of communism.
ohhh, oil... evidently, that's our only motive for doing anything internationally. if we wanted oil, we would've gone in all by ourselves. if I'm not mistaken, the UN saw Saddam pulling some pretty illegal shit. Article 51 of the UN Charter says that one state has no right to abrogate the territorial sovereignty of another state. Iraq invaded another state in an effort to reclaim a former province. What if we (the world) just let that happen? Then you would see China immediately try to take back Taiwan (they did nothing with their UNSC vote on Iraq in the '90s, but chose to abstain instead). By not doing anything in Iraq in '91, the UN would have essentially rendered itself useless by not punishing a country who directly violated its charter.