What Is The Approximate Distance Between Thailand And The United States?

Depends where you want to go in the USA.

From Bangkok to San Francisco is about 17 hours flying time, or a bit over 10,000 miles. If you only want to go to Hawaii, you could get on US soil from Thailand about 5 hours earlier (only 7,000 miles).

The distance from the centre of the USA to the centre of Thailand is nealry 12,000 miles.

I'm going to revise that.

From Bangkok to Alaska can be as little as 5500 miles. Going the same route (over Alaska) you can get from Bangkok to the centre of the USA in as little as 8500 miles. But the actual flights tend not to go that way, because it's over politically sensitive airspace where few Air Traffic controllers reside. So the longer distance is more typical for travellers.

1400