The M-1 was called 'the greatest battle rifle invented' by no less than Patton, and was the US' main battle rifle from ~1936 through ~1968 (including the M-14, which was a successor-model) when it was replaced by the M-16.
Mommy Gummint here said "No, thanks. You may NOT sell those rifles in the US."
Best part: their "rationale"
“The U.S. insisted that imports of the aging rifles could cause problems such as firearm accidents. It was also worried the weapons could be smuggled to terrorists, gangs or other people with bad intentions.”
Importers of the rifle would eventually sell them ONLY to licensed dealers (FFL's). There are a helluvalotta regs about selling rifles to terrorists and gangs, making such sales ILLEGAL.
"Accidents"? Has nothing to do with the age of the rifle. Has only to do with brainfarts of users.
It's a sign......