According to Senator Edward Kennedy, we are now in a seemingly intractable quagmire, a judgment that is rejected by General George Casey, the US military commander in Iraq.

NPR: Scoring the War in Iraq: Who's Winning?

His has been a triumph of ambition over intractable matter, a fulfilment of Mahler's faith in Arthur Schopenhauer's idea that the human will can overcome any force on earth.

ECONOMIST: Gilbert Kaplan

On the other hand, the way opposing political parties and leaders managed to work alongside one another in both Zimbabwe and Kenya has shown there is a way of resolving what might appear to be intractable problems without holding a country to ransom.

BBC: Letter from Africa: Kenya fuels poll optimism