Last week, after a decade of U.S. military presence in Afghanistan, President Obama announced a plan to begin withdrawing thousands of U.S. troops from the country this year. The war has been expensive -- a Brown University research project released Wednesday estimates the total cost of the U.S. wars in Afghanistan and Iraq at nearly $4 trillion (a figure that includes the ongoing cost of veterans' care). The human cost is more difficult to quantify, as more than 2,500 coalition troops (1,644 of them American) have now been killed, and civilian casualties are estimated at well over 100,000. Canadian combat operations in Afghanistan will end in July, as troops withdraw from the southern region and hand control over to U.S. forces. Just yesterday, a group of nine Taliban suicide attackers stormed a major hotel in Kabul that was popular with foreigners, killing 21 and raising fears of what may come as foreign troops depart the country. Gathered here are images from the ongoing conflict over the past month, part of an ongoing monthly series on Afghanistan.