John Walker Lindh of California is asking President Bush to commute his 20-year prison sentence for aiding the Taliban in Afghanistan. The 23-year-old U.S. citizen was detained three years ago in Afghanistan and was accused of fighting against U.S. troops. Lindh’s attorney said yesterday that his client’s sentence should be reduced now that Yaser Esam Hamdi is being released after being held for three years as an enemy combatant. Hamdi is also a U.S. citizen who was detained in Afghanistan. Lindh’s attorney said “Comparable conduct should be treated in comparable ways in terms of sentencing.