I think a little differently. The sanctions were going to be imposed, so he has less to risk by kidnapping the British.
I am just on the outside, but having read what's been going on inside Iran and Iraq, I am convinced that this is an effort either to divert our attention from being hard@$$es in Iraq when it comes to finding Iranian military or diplomatic personnel or to create an embarrassment to create pressure to get us to back off.
He ridiculed the UN. He ridiculed diplomacy. He then launched a diplomatic charm initiative that turned the left on his side (recall the luv-notz from DU).
Years ago, there was a play from a Swiss playwright, Max Frisch, Biedermann und die Brandstifter (1953) (translations, The Firebugs (US)/The Fire Raisers (UK)). Basically this ordinary guy befriends someone who is openly going to commit arson, but the ordinary guy can't bring himself to challenge the arsonist and even goes out of his way to help him. Frisch had the terrorists pegged.
You see, I dont believe that Iran wanted to do this, but had no choice, considering current events in the region.
Remember, the Brits were taken while they were inspecting a ship headed for Iran, when they were taken prisoner.
The million-dollar question?
Just what the hell was on that ship?
The answer to that question will determine the future. I think Iran could not afford to have whatever was on that ship discovered by the coalition.
Funny how nobody is talking about that, huh? Total blackout on that subject tells me all I need to know.