The Taliban for now have no chance of defeating Afghanistan's Western-backed government but the insurgency is sapping support for President Hamid Karzai who is facing his most difficult days since coming to power in 2001.
Karzai won a presidential election in 2004 with more than 50 percent of the vote. But the optimism, also generated by last year's almost trouble-free parliamentary polls, has evaporated.
Many Afghans are frightened, despondent and angry about a revitalised Taliban insurgency raging in the south and east, analysts say.
The pressure on Karzai is mounting as Nato prepares to take over security from US-led forces in the Afghan south. Nato countries with troops in the firing line could soon be making much greater demands on him than a tolerant United States has up to now.