The Navy's SEAL Team 6 ... best known for killing Osama bin Laden, has been transformed by more than a decade of combat into a global manhunting machine. That role reflects America's new way of war, in which conflict is distinguished ... by the relentless killing of suspected militants. While fighting grinding wars of attrition in Afghanistan and Iraq, Team 6 ... joined Central Intelligence Agency operatives in an initiative called the Omega Program, which offered greater latitude in hunting adversaries. Team 6 has successfully carried out thousands of dangerous raids that military leaders credit with weakening militant networks, but its activities have also spurred recurring concerns. Afghan villagers and a British commander accused SEALs of indiscriminately killing men in one hamlet; in 2009, team members joined C.I.A. and Afghan paramilitary forces in a raid that left a group of youths dead and inflamed tensions between Afghan and NATO officials. When suspicions have been raised about misconduct, outside oversight has been limited. This is an area where Congress notoriously doesn't want to know too much," said Harold Koh, the State Department's former top legal adviser. Like the C.I.A.'s campaign of drone strikes, Special Operations missions offer policy makers an alternative to costly wars of occupation. But the bulwark of secrecy around Team 6 makes it impossible to fully assess its record and the consequences of its actions, including civilian casualties or the deep resentment inside the countries where its members operate.