the largest conventional weapon the u.s. has ever deployed in combat, targeting isis. afghan commando patrols with u.s. support combing through the area now. assessing the damage, and searching for information. tonight, the questions, what did the strike accomplish, and at what cost? terry moran in london tonight. reporter: the pentagon video shows the immense destructive power of this weapon, devastating an entire mountain valley. the boiling plume of smoke quickly turning into a mushroom cloud, rising over the massive blast area. take another look. the quiet valley, then you can see the bomb falling there, guided by internal gps right to the target. the tremendous explosion. and you can actually see the blast wave radiating across the landscape. afghan villagers miles away said they could feel the earth shake when it detonated. [ speaking foreign language ] reporter: my house was shaking after the blast, this man said. the whole area was burning on fire.
bobby schneider. for now west to hawaii, japan s prime minister is set to visit pearl harbor with president obama today, marking the first time in decades one of the country s prime ministers has visited the historic site. shinzo abe arrived in hawaii yesterday for a trip intended to show a strong alliance between his country and the united states. following his arrival, mr. abe visited the national memorial cemetery of the pacific which honors those who died while serving in the u.s. armed forces. while the prime minister s visit to pearl harbor has been widely reported as a first ever since world war ii ended, he actually will be the fourth prime minister to do so. that includes a visit by his grandfather who also served as prime minister. japanese officials are characterizing mr. abe s visit to the site as the first by a sitting prime minister with a u.s. president. this trip comes seven months after president obama became the first sitting president to visit a park dedicated to the