Mexico’s Day of Infamy

When Italy declared war on Britain and the other allies in 1940, several Italian merchant ships did not receive notice in time, and were in neutral ports. Under the Law of the Sea, they were seized by the governments of the neutral nations in whose ports they happened to be… one of those Italian ships being an oil tanker in Mexico. Britian and the US, having attempted a boycott of Mexican oil after the expropriation of 1938, had only recenly resolved their disputes with Mexico, and — while for a very short time following the rift in relationships, it ha sold oil to the Germans and Italians — the country’s foreign policy had been anti-fascist, Mexico being the only nation in the League of nations to stand up for Ethiopia when Italy invaded that country, and had been one of the few to openly support the Spanish Republic.

Despite Mexican neutrality, it stopped selling oil (and had only done so clandestinely) to the Axis, and while maintianing neutrality (Mexican consulates and embassies in the occupied and fascist countries serving to facilitate refugees and even protecting allied citizens trapped in those countries) and providing material assistance to the allies… especially oil.

With the US declaring war in December 1941, it was only a matter of time until Mexico would be forced to declare war. When the Potrero de Llano was sunk by a U-boat on 13 May 1942, Mexico declared war on the Axis the following day.