There are those here in the UK who state - quietly - that Karzai is the only option and a far larger group who'd prefer the question was not even asked. It is sometimes bewildering to see how the fundamental issues of our role in Afghanistan are pushed aside for the tactics.

I would expect the 'establishment' would swiftly change its "tune" if the USA announced, or quietly undermined him, that Karzai was an obstacle.

From my "armchair" Karzai is not the only option, especially when you realise the power of a nation-state based in Kabul is actually very limited.

IMHO we should not overlook the domestic impact of Karzai's recent apparent statements, his attitude will harden the majority here who oppose the UK involvement and could swing others.