Philip H. Gordon, writing in Foreign Affairs:

It can, but only if US officials start to think clearly about what success in the war on terror would actually look like. Victory will come only when Washington succeeds in discrediting the terrorists' ideology and undermining their support. These achievements, in turn, will require accepting that the terrorist threat can never be eradicated completely and that acting as though it can will only make it worse.

Can the War on Terror Be Won?