From a scaffold stairway that led from the North Dakota’s conning tower, the President stepped heavily onto the concrete floor with a grunt. A large-framed man who hated confined spaces, he was thankful the interior tour was over. At least it had been cooler inside the submarine. With the economy a mess and Congress mired in another deadlock, visiting a shipyard seemed like the last priority on his agenda, but he had promised the Secretary of the Navy he would go boost the morale of the ship workers. As a small entourage flocked to catch up with him, he suppressed his irritation by marveling at the sub’s dimensions.

“An amazing feat of construction.”

“Yes, sir,” said a blond-haired man in a tailored suit who hung at the President’s elbow as if attached by a string. “She’s an impressive feat of technology.” Assistant Chief of Staff Tom Cerny had specialized in defense issues on Capitol Hill before joining the administration.

“She’s slightly longer than the Seawolf class boats, but downright minuscule compared to a Trident,” said the tour guide, a chipper Electric Boat engineering manager. “Most people are used to seeing them in the water, where two-thirds of their bulk is hidden from view.”

The President nodded. As it lay on huge supporting blocks, the three-hundred-and-seventy-seven-foot-long hull towered over them.

“She’ll be a great addition to our arsenal. I thank you for giving me the opportunity to see her up close.”

A granite-faced admiral named Winters stepped forward.

“Mr. President, while we were happy to have you preview the North Dakota, she was not the reason we asked you up here.”

The President took off a white hard hat affixed with the presidential seal, handed it to the admiral, and wiped a bead of sweat from his forehead.

“If a cold drink and a touch more air-conditioning can be worked into the bargain, then lead on.”

He was escorted across the building to a small door guarded by a uniformed security man. The door was unlocked, and the presidential group led in one by one, their faces captured by a video camera above the sill.

The admiral flicked on a bank of overhead lights, illuminating a narrow bay that stretched nearly four hundred feet. The President saw another submarine in a state of near completion, but this vessel was like nothing he had ever seen before.

Roughly half the size of the North Dakota, it sported a radically different design. Its unusually narrow jet-black hull tapered sharply at the bow. A low, egg-shaped conning tower rose just a few feet above its top deck. Two large streamlined pods were affixed close to the stern, almost in the shape of a dolphin’s tail. But the most unusual feature was a pair of retractable stabilizers, shaped like triangular wings, that stretched from either side. A pack of four large tubular canisters clung to their undersides.