Amid the shock and horror of what happened on Sept. 11, 2001, a group of ordinary Americans became heroes by sacrificing their own lives to save others.

A monument to them, the passengers and crew of Flight 93, exists in south central Pennsylvania. It is at the site of where their airliner crashed, killing all 40 of them along with the terrorists who planned to dive the plane into a target in Washington, D.C.

What they did, on a day when evil seemed almost unstoppable, reminded Americans of why we will prevail in the war against Islamic terrorists.

Now there is a new monument. It is one of which both Americans and our adversaries should be aware, for very different reasons.

It is the USS Somerset, a 684-foot-long Navy vessel that will be put into service Saturday. Named for the Keystone State community near where Flight 93 went down, the Somerset is packed with tributes to the heroes who fought back against their captors.

Someone in the Defense Department thought carefully in deciding on a ship to honor the Flight 93 heroes. The Somerset is referred to by the Navy as an “amphibious transport dock.”

That means she carries troops, helicopters to carry them into battle, tilt-rotor aircraft and assault watercraft to support them. In other words, the Somerset is precisely the type of vessel from which lightning-fast assaults against terrorists and their bases would be launched.

Let us hope she and her crew, memorializing the Flight 93 heroes on one hand and avenging them on the other, have very successful careers.