It is a delicate situation. But the Iranians have also seized U.S. personnel in the past. What does that tell you of their 'respect' for the U.S.? The Iranians are opportunists full-stop. They have had a lot of success in embarassing Western states in the past (e.g: U.S. Embassy incident). But they'll be smart enough not to push their luck in the current climate. Last time they seized some U.K personnel (and briefly U.S. on another occasion)these were released quickly in this regard. The UK government will never release prisoners in exchange for these men (just see the UK and US condemnation of the Italian capitulation in Afghanistan recently).
The key words were "in the past". Try that shit with us now and you know that we will eliminate their naval forces and begin a war with Iran while we are planted on 2 of their borders.
The last incident you refer to was in 2003 and it's obvious our priorities were elsewhere, but this time around it simply gives us the excuse we need to put their regime out of business permanently.