Legal issue with "neutral" Americans in other nations' armed forces

What was the legality of it? Per se if you're neutral you're not supposed to fight, right?

The AVG pilots and ground crews serving in China immediately comes to mind.

But we know before America's entry into WW II, twelve Americans joined the King's Royal Rifle Corps (old 60th) with half as officers and half as enlisted.

We also know there were a handful of Americans who fought RAF. Did they say they were Canadians to slip in? There were three RAF Eagle Squadrons that were later absorbed into the Army Air Corps.

The strangest is Americans who moved to Russia in the '30s. It was part of Henry Ford's assistance to modernize Russia by setting up a Ford Factory there. Many of his employees took their families to the CCCP and I know of at least one kid who grew up in time to serve in the Red Army as an American.

After America's entry into the war it wasn't such a big deal anymore. I've heard of an escaped American PoW who joined a Russian tank column and fought with them. He survived the war.

So, before America became a belligerent, how did these Americans slip by?

 

good topic--thanks
.....I've got Chennault's book somewhere around here--I'll have to do a proper search for it....had it since around the early 1970s----I got it on '''loan'' from the library---''''forever'''' ...[ maybe the Seinfeld library officer will find me someday--ahahhahahahha ]
....but a quick search says the AVG's first combat was after Pearl Harbor.....? also, it did not matter much because the Japanese did not follow the Geneva Convention/etc ......?
...what do you mean by ''slip by'''?
...were they ''legally'''/''officially''' citizens of the countries they fought for--through some ''symbolic''' oath?
...couldn't matter much since there weren't many per capita......?

 

Ford workers were a very small part of the thousands of Americans that went to the USSR which began in 1931. All went there because of Soviet job offers and the supposed "workers paradise", while the US was sliding deeper into the Great Depression. This exodus was soon curtailed by the Soviets as the number of American applicants far outnumbered Soviet jobs & housing. Most that went and stayed died in Stalin's Great Purge of the late 30s.

 

As to the AVG, everything was bought and paid for by the Chinese, from the planes to the salaries. It helped that this was done with a nod and a wink from the US government. Also why military personnel had to resign first, before signing on with the Chinese.