Forgotten Wars

In 1859 Lyman Cutlar, one of 25 American settlers on the disputed island of San Juan, shot and killed a pig he found rooting around in his garden. The pig belonged to the UK's Hudson Bay Company and when British authorities threatened to arrest Cutlar, the American settlers called on the protection of the US military. It sparked a major military face-off between the two nations, which had British warships lining up outside San Juan harbour...

While the only casualty in the San Juan incident was a pig, the 1871 Korean War was sparked by trading disputes with the US and the massacre of the crew of an American merchant ship. Then there's the bizarre episode of one US citizen with an outsize ego. He single-handedly tried to seize control of Nicaragua.

These and a series of little-publicised American military incursions into Russia, Central America and the Caribbean make up a whole lot of Forgotten Wars.