Fact check: After Pearl Harbor, Japanese didn't invade US because they feared armed citizens?

History quiz: 

After Pearl Harbor, did the Japanese refrain from invading the mainland United States because they feared there were gun-savvy Americans in nearly every home?

That’s the claim of a 20-paragraph post on Facebook that has been shared more than 21,000 times. 

The post argues that America is safe from invasion because of gun-owning hunters. It starts its historical claim by stating:

"After the Japanese decimated our fleet in Pearl Harbor Dec 7, 1941, they could have sent their troop ships and carriers directly to California to finish what they started. The prediction from our Chief of Staff was we would not be able to stop a massive invasion until they reached the Mississippi River. Remember, we had a 2 million man army and war ships in other localities, so why did they not invade? After the war, the remaining Japanese generals and admirals were asked that question. Their answer....they know that almost every home had guns and the Americans knew how to use them."

This post was flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Facebook.)

It’s not a new claim. In a video posted in 2012, Ed Emery, a Repubican state senator from Missouri, claimed that it is known that Japan was deterred not by America’s armed services but because "every American was armed."

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Four experts told us there is no evidence that Japan ever seriously considered such an invasion and that military limitations, not Americans armed with hunting weapons, were the reasons why.

We rate the statement False.