There are questions about why the British sailors and marines conducted themselves in the way they did during captivity, and the British military will be taking up these questions, no doubt, in the coming days. But some of the declinism baloney on the Right (and Left) has gotten a bit nuts.
Peter Scoblic says let's just all relax for a moment:
The specter of Western decline is an old conservative and neoconservative trope that wasn't true during the cold war and is even less applicable now. Great Britain has two active carrier battle groups and spends more on its defenses than all but four countries, lagging significantly behind only the United States and China. It also deploys 16 megatons of nuclear explosives on its Trident submarines. That's about 1,000 times the power of the bomb that destroyed Hiroshima. Put it this way: If British leaders woke up one day and decided that Iran should no longer exist, Iran would no longer exist.
Reading some of the commentary on this matter, you'd conclude that Iran was going to regularly start challenging the British Navy as a result of the propaganda victory it scored here. I'm not holding my breath.