I think that is a good contrary example; thank you for reminding me.
Although I regard it as less a "war" (which I associate more with duration and cost) and more of a military action (akin to Grenada or Panama), there was very acute and certain ECONOMIC damage to the US (as a whole, not to a few oligarchs) if we had not stepped in as we did. So we arguably had much more to lose than the Iraqi people had to gain.
Notably in addition to the specific - economically worthwhile - agenda, it was of very short duration, and we - wisely - didn't pursue Saddam beyond throwing him out of Kuwait (our major oil source).
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http://www.defense.gov/News/Feature-Stories/story/Article/1728715/desert-storm-a-look-back/
Operation Desert Storm was the first major foreign crisis for the United States after the end of the Cold War.
On Aug. 2, 1990, Saddam Hussein led a well-equipped Iraqi army into Kuwait, a major supplier of oil to the United States.
The U.S. had supplied Iraq with military aid during its eight-year war with Iran, giving Iraq the fourth-largest army in the world at that time. This posed a threat to Saudi Arabia, another major exporter of oil. If Saudi Arabia fell, Iraq would control one-fifth of the world’s oil supply. The Iraqi leader also was repeatedly violating United Nations resolutions, so the U.S. had U.N. support in responding to Iraq’s invasion of Kuwait.
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