If you could only have one semi auto hand gun say under $1500 for self protection uses which would it be? Size, concealment, shooting deer on occasion, experience etc. doesn't matter. What is your choice if able to pick one semi auto gun for general defense here in the US? (Emphasis Mine)
Emphasizing both self protection, and occasional hunting use on animals up to deer size there are 3 options I like.
1. A pistol in 45 ACP, capable of, and with the parts for a 45 Super conversion. 45 Super for hunting, 45 ACP for all other general use.
2. A pistol in 10mm, with a 40 S&W bbl fitted. 10mm for hunting, swap in 40 S&W bbl for general use.
3. A pistol in .38 Super, with a 9mm bbl fitted. .38 Super, which gives .357 Mag ballistics even with heavier loads, for hunting, swap in 9mm bbl for general use.
Pistols, off the top of my head that meet these requirements - 5" 1911 in any of the calibers listed first in each respective combo; Glock 20 in 45 ACP, 21 in 10mm; HK USP (fullsize) in 45 ACP, SIG P220 in 45 ACP; CZ 97 in 45 ACP; S&W 1006 in 10mm, or equivalent fullsize metal frame auto in 45 ACP. There are others I can't think ofthat are probably capable of one of the 3 combos.
I'd go handle as many of those as I could. See what pistols fit your hand, and which ones you shoot best. Those are my general suggestions for full versatility in both everday and hunting use. The hotter of the two calibers in each combo, while commercially loaded, are much more economical when handloaded. Very good pistols all three base calibers are available for well under $1000 which allows room in the budget for spare mags, holster, and a reloading press if you're so inclined. I like 1911s and will likely try the 45 Super conversion on my base Springfield when I return from overseas. Hopefully the caliber combinations I listed are helpful.