Marines pushed into the Taliban stronghold of Marja, in southern Afghanistan, Saturday, and met stiff resistance from bands of insurgents, as well as tough terrain. Working with Afghan soldiers, the Marines slowly cleared roads of improvised bombs and trudged through muddy ground laced with irrigation canals in this rural area that’s home to 80,000 people. This is the largest coalition effort since the Afghan war began. One Marine was killed and several were injured, but it’s unclear how many enemy fighters were killed by the ground units or the missile strikes fired by drones. The area is thick with mines, making progress slower. Marines tried to detonate roadside bombs by firing rockets that laid a line of explosives in front of them, but still they met 15 bombs in the three-quarters of a mile from their command post to a canal. Logistical vehicles got hung up in mud while insurgents fired on the Marines. The goal is to create a “security bubble” so reconstruction professionals and government officials can begin work in Marja.