Oh, gimme a fucking break.
There are many, many reasons that the Japanese did not invade the United States, and the level at which our citizens are armed ranked somewhere below "not enough domestic rice, sake, and sushi production."
The Imperial Army and the Navy couldn't even agree on a war plan, so they changed the focus of their efforts three different times in the 6 months following Pearl Harbor. At no time was there any serious discussion of mounting an invasion of the United States, and the problem wasn't guns in the hands of the citizens - it was oil and shipping.
And seriously - whoever the fuck this Larry Pratt is with the "Gun Owners Association", he needs to back away from the crack pipe.
"Why does your report make no mention of the fact that as many as 2,500,000 Americans use guns every year in self-defense?"
The only possible way that figure can be correct is if you include people defending themselves from Daffy, Bugs, and Bambi.