alternatehistory.com

In 1886. US forces mounted expeditions into the Mexican states of Sonora and Chihuahua, as part of the Geronimo Campaign. This had the tacit approval of the Mexican Governement. One of these expeditions brought US Army Captain Emmet Crawford and his Apache Scouts into Mexico.
During this particular expedition, Mexican forces wounded several US personnel and killed Captain Crawford. This incident became known as the Crawford Affair. Some say this almost started another war between Mexico and the U.S.

What if the incident had gone worse for the US and the incident escalates into a full-scale war?

What happens?
Does the US Army unleash the cavalry against Mexico in a punative raid or does it become a full scale war?
Is there the political will in the US to commence such a conflict?
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