It amazes me that people's patriotism goes so far as to pushing them into buying inferior products simply because they're stamped with "MADE IN USA." I try to avoid any goods which I don't know for a fact are top-notch products, regardless of where they're made. If a company sounds-off too much about "MADE IN USA" it sets off some alarms. If they have to push that fact, chance are it's not a very well engineered or constructed product that can stand on its own.
I gather it's a different mentality and it's why companies like Chrysler, Ford, and especially GM are still in bussiness, producing all-around the worst automobiles of the past 20 years.
So, if it matters to people... TUSA (Tabata USA) is a Japanese company and their products are made in Taiwan, Japan, etc...
APEKS (not APEX according to someone above who who preaches the DIR cult lines but doesn't know about the kit), is from the UK (their regs are confirmed to be made in-house, in the UK, check specifics on BCDs for possible outsourcing of components)
Mares, Dacor and Cressi-Sub are Italian.
It doesn't take long to find corporate web pages and figure out the origins of a company. To check individual items you may have to send an email or check the actual item.
If you want to buy the best all-around gear, for you, then you will have to broaden your choices beyond the USA. If you just want to buy all-American, then that's fairly simple, but you might end up with less than ideal pieces for your purposes.