Iranian hostages
There are several reasons why Iran, or a particular sub-group in Iran such as the Revolutionary Guards under Pres. Ahmedinejad, might want to deliberately kidnap British soldiers:
1. They find it very irritating that British forces are constantly patrolling close to their borders in the Shatt-al-Arab waterway; 2. It seems less dangerous to them than capturing US servicemen; 3. They want to take attention away from their nuclear program and the UN sanctions; 4. They want to gain domestic support within Iran for their aggressive anti-Western policies. 5. They seek to be the leading anti-Western force within the Muslim (including Arab world).
It was incredible that while Iran is a major threat to the Sunni Arab countries, there was an official Iranian Govt. representative at the just concluded Arab League meeting in Riyadh. These meetings are so constricted due to the need to pass any resolution unanimously among 22 Arab countries, that nothing can be agreed except the most generally accepted topics, such as their opposition to Israel. That is why they unanimoulsy reaffirmed the 2002 resolution of the Saudi Plan without change, because they could not agree on any changes. Since this version of the Plan was rejected by Israel 5 years ago, in effect on the surface nothing has changed. Yet, the taking of the British military hostages puts Iran at odds with most of the Arab countries, but this was not publicly discussed at Riyadh, and neither was the terrible Sudan-Darfur situation.
Meanwhile British PM Blair is gradually upping the ante, promising consequences if Iran does not immediately release the 15 servicemen (including one woman who the Iranians seem to have fastened onto to use for PR purposes). It is not clear what can be done, since just as in the case of the Israeli captives, one false move and their lives become forfeit. This is another hostage crisis that will drag on, and a legal case may be brought by the Iranians against the hostages. But since the British were operating as part of the Coalition forces under UN auspices, neither the British nor the US can accept this illegal Iranian act of aggression.