[varjag]

I don't think "US knows it" is how border safety works. Either way I fail to see your point how that would be different with China.

As to motives, who knows. Iran could be trying to move confrontation from economic to military, where it has a shot on regional parity. With all talk about Bolton, Iraq, Vietnam and on this admin is very docile. Iran came out on top from this confrontation, bolstering its regional influence, so why not.

[pwodhouse]

Iran has zero ability to win a regional war against the US, unless you consider bombing Israel to be critical damage to the US, or if the US has no stomt for Iranian casualties.