Look like the usual wingnut sources. I've heard of the Federalist, so I checked it out for fun. I read it, then just in case I missed something, I cntl-f searched it for the word "mail". Nope, didn't miss it. "Sign up for our email edition." It's about in-person fraud, which it also concluded statistically isn't a real problem. My favorite mikezpen line was "Yet we are expected to believe that, unlike violent crime, voter fraud is limited only to the cases that are actually reported and prosecuted? This is a senseless position." We can't find it, BUT THAT JUST PROVES IT'S OUT THERE!
Just to recap, almost every military vote for several generations is cast by mail. Chew on those implications.