Customs has no real interest in what currency you've paid... But paying BTC for USD invoices - it happens all the time, already.
I just looked up some numbers and it appears that 'the USA' paid around 37.5 TRILLION bucks for Chinese imports last year.
Global trade of course would be a number much greater than this, probably 50x larger.
Obviously the officials in government aren't going to buy bitcoin to do trade with anyday soon, but businesses like walmart would save Billions every year if they started paying for imports in
BTC.
If what you say is accurate, then the little guys already have an advantage over the bigger guys in paying for all of their shipments with
BTC, which will either make them into the bigger guys, or at least make their competition use
BTC to compete. Eventually, it can't help but to trickle up to the largest of corporations, pumping several tens of Trillions of USD's worth of wealth into bitcoin.
Twelve Trillion USD invested in
BTC with a 12 million
BTC supply would be a $1 Million bitcoin.
...And that's without any user adoption by the people on the street; not even a single merchant accepting them.
WHAT IS STOPPING THIS AND HOW DO WE DESTROY THAT?