It's been suggested that theology isn't actually a subject at all. But if that's the case it has a huge advantage over many other disciplines: being qualified in theology gives you the authority to speak out on subjects that have nothing whatever to do with the number of angels that can dance on the head of a pin.
The muddle-headed cleric was interviewed for about eight minutes in advance of a debate in the House of Lords. The essence (indeed the whole) of his thesis was "something must be done."
I've nothing against people having opinions, but when they appear on national media to speak on a particular topic, I expect them to have some established expertise, authority or at least relevant experience that will add to the debate. But just because Dr. Williams is a nice chap with a posh voice - that's not a good enough reason to put his views on the nation's premier morning news radio programme. If you listen to what he said in those eight minutes, you'll find he said nothing new or useful.