There's a major distinction, however, in that it's a heck of a lot harder to safely and reliably lug briefcases or suitcases full of $100 bills from Chicago to Tehran, than it is to click and transfer some Bitcoin. Which is the whole point.
(Definitely in Iraq and Afghanistan, I don't know if there's any back channel deals at the moment paying off Iranians in 100$ bills but I wouldn't be surprised if we were nudging for regime change by funding revolutionaries)
The topic here is sending money across sanctioned borders, not local circulation.
> The Wall Street Journal reported, saying the hidden conduit enabled Tehran to receive up to $8.4 billion last year.