Focusing back on the original poster's question... and I admit I haven't read all of the other 40+ responses so far.
The .380 auto can do the job, with the right load, in the right gun, and proper shot placement. ANY gun can be intimidating, and any gun is better than no gun in a bad situation. Also, unless you're willing to strap on some big magnum, or carry a shotgun, the issue of stopping dead-in-his-tracks a 6' 3" giant drugged out bad guy with armor-plated clothing just isn't going to happen.
Every choice on gun, load, holster, etc. is a best compromise. I live in South Florida, and heavy clothing just isn't in the mix. That goes for both legal carry people as well as the bad guys.
I've got a couple of carry gun options. Most DAYS, a 442 (.38 Special), or a Sig P238 (.380 auto). It's difficult to conceal anything too big wearing shorts and a lightweight shirt. When I'm out at NIGHT, dressed up a little bit, a SW99 in .40 comes along.
The new compact 9mm guns are a good option too. I just haven't strayed from what I've found to be comfortable and practical.
Best wishes, and remember... get a good holster (or holsters) for your choice of carry... whatever you choose.
Roger aka Mr. Wonderful