Fifteen
I also find the British claims as to the location of their sailors and marines a bit more compelling than the Iranian; the Iranians changed their story about the location after the British pointed out that the first Iranian claimed location was, in fact, in Iraqi waters after all. But whether the sailors were in either Iranian or Iraqi waters is a bit beside the point. The border between Iran and Iraq in this area is confusing and oft-disputed, and arresting the British sailors in disputed waters is not an appropriate reaction even to what may have been a small incursion. Especially since Iran is not contesting the basic British account (that the sailors and marines were investigating an Indian merchant ship), the arrest and detention would be a major over-reaction if it happened anywhere else in the world.
It seems obvious to me that the arrests are intended to be seen as a political response to US detention of Iranians in Iraq, and perhaps as a means of embarassing the Blair government. The method of capture (several Iranian boats acting in concert) would seem to support this. The byzantine nature of the Iranian state leaves in question who, precisely, intends to send what political message. The entire situation is worrying, though, because this is hardly the time for Tehran to act recklessly against the major US ally. The drumbeat of war against Iran has slowed in the last few months, and since I don’t want war I would prefer that Tehran refrain from presenting convenient casus belli. Unfortunately, Iran also has a Dick Cheney, a Don Rumsfeld, and a Bill Kristol; men who believe that the “enemy” understands only force, and who habitually underestimate the costs of such an approach.