My votes for the dumbest wars of the Millenium:
The War of the Pacific (1879-1884): Chile and Peru fight a long and bloody war over…Birdshit! It took them until 1929 to agree on what country owned what birdshit!
The Soccer War (1969): Fought between El Salvador and Honduras over a disputed World Cup playoff game. 3,000 killed in four days of heavy combat!
War of Jenkin’s Ear (1739-1743): England started a four-year war with Spain in reaction to a Spanish bureaucrat’s mistreatment of a slave smuggler. (Okay, maybe not so much a dumb war, as much as a dumb name for a war.)
Any other candidates?