An enormous, expensive and technology-laden warship that some Navy leaders once tried to kill because of its cost is now viewed as an important part of the Obama administration's Asia-Pacific strategy, with advanced capabilities that the Navy's top officer says represent the Navy's future.

The stealthy, guided-missile Zumwalt that's taking shape at Bath Iron Works is the biggest destroyer ever built for the U.S. Navy.

The low-to-the-water warship will feature a wave-piercing hull, composite deckhouse, electric drive propulsion, advanced sonar, missiles, and powerful guns that fire rocket-propelled warheads as far as 100 miles. It's also longer and heavier than existing destroyers -- but will have half the crew because of automated systems.

The General Accounting Office expressed concerns that the Navy was trying to incorporate too much new technology. Some Navy officials pointed out that it's less capable than existing destroyers when it comes to missile defense, and a defense analyst warned that it would be vulnerable while operating close to shore for fire support.

Even its "tumblehome" hull was criticized as potentially unstable in certain situations.

The 600-foot-long ships are so big that the General Dynamics-owned shipyard spent $40 million to construct a 106-foot-tall building to assemble the giant hull segments.

And then there's the cost, roughly $3.8 billion apiece, according to the Navy's latest proposed budget.

Including research and development, the cost grows to $7 billion apiece, said Winslow Wheeler, director of the Straus Military Reform Project at the Center for Defense Information in Washington.