A two-hour seminar on the complex, multibillion-dollar U.S. Navy shipbuilding program took place on Capitol Hill recently.

It illustrated the issues that Pentagon officials face when dealing with current financial and political pressures while guessing what the military threats will be 20 and 30 years into the future.

The seminar professors were Sean Stackley, assistant secretary of the Navy for research, development and acquisition, and Vice Adm. Terry Blake, a deputy chief of naval operations with a fancy title who is really the service’s chief budget officer.

The students were lawmakers on the House Armed Services subcommittee on seapower and projection forces.

Subject of that day: President Obama’s $13.5 billion fiscal 2013 shipbuilding budget. The students had many questions, and Stackley and Blake offered frank, clear answers.

Patriotic bunting graces the amphibious transport dock ship San Diego, LPD 22, at Northrop Grumman Shipbuilding's shipyard in Pascagoula, Miss., in 2010, where it was under construction. (Harlan Kirgan/AP Photo/The Mississippi Press)

First, Stackley provided background that showed the amazing number of ships being built and future plans. The Navy today is “a battle force of 282 ships, nearly half of which on any given day are underway performing missions around the globe,” he said.

Over the past year “two destroyers, a submarine [and] a dry-cargo ammunition ship have joined the fleet.”

He added that the amphibious assault ship USS San Diego will be commissioned this spring, along with six other ships.

He also noted that “keels have been laid” for the lead ship of the DDG-1000-class destroyer ($3 billion); plus the next littoral combat ship ($48.7 million); another Virginia-class nuclear attack submarine ($2 billion); and the next cargo ship.

Since December 2010, contracts have been awarded to procure 38 ships. That number grows to 40 shortly with the award of the next-generation large-deck amphibious assault ship, as well as the final ship of the earlier-version amphibious assault ship.

The fiscal 2013 budget seeks 10 additional ships. But that actually represents a reduction of $1.5 billion and one ship from this year because of cuts required by the 2011 Budget Control Act. Since Navy ships take years to build, reductions next year affect future shipbuilding, starting with fiscal 2014.

Rep. Todd Akin (R-Mo.), chairman of the subcommittee, asked about a planned Virginia-class nuclear attack submarine that was being pushed from the 2014 fiscal budget to the fiscal 2018 budget. That move broke a pattern of buying two a year with target prices of $2 billion each. It saves $200 million or more per submarine and stabilizes the shipyards building them.

“Is there some way, perhaps, that we could try to move that up so we stay on that two-year build cycle?” Akin asked.

Stackley explained that other priorities within the fiscal 2014 budget made it impossible to fund another Virginia submarine and another destroyer that year. Don’t be surprised if Congress comes up with funds for the slipped submarine.

Akin asked: If there were more shipbuilding money available, would “the first thing you get [be] an extra submarine?”

Stackley’s reply: “Yes, sir.”

Rep. Rob Wittman (R-Va.), whose district includes Newport News, home of the shipyard building the new aircraft carrier USS Gerald R. Ford, noted that of the 91 ships to be built over the next 10 years, 31 are to be smaller Littoral Combat Ship Class (LCS) vessels.

Wittman said: “I understand the budget restraints that we’re in right now. . . . [But] is this [emphasis on LCS vessels] in the best interest of national security?”

Stackley explained that LCS vessels fill “war fighting gaps” around the world, where their effectiveness in relatively shallow seas gives them capabilities for surface warfare.

He then pointed out that destroyers are now performing operations and responding to events “that an LCS in theater would be quite suited for.”

Stackley noted, “We have a high-end, roughly 300-man crew on a $1.5 billion warship [a destroyer] responding to an issue that we’d really prefer a $500 million ship with a 75-man embarked crew [an LCS] taking care of.”

Rep. Rick Larson (D-Wash.) asked whether the decision to delay procurement for two years of the new Ohio-class strategic submarine was made in conjunction with U.S. Strategic Command, which runs the nation’s nuclear intercontinential ballistic missile operations.

Stackley said the command “was fully involved in the decision,” which slipped the first new submarine from fiscal 2019 to 2021.

He explained that in the 2030s there would be “a temporary reduction to 10 available SSBNs,” or strategic submarines, rather than the planned 12 for the second half of this decade.

Of course, who knows what the requirement for nuclear warheads will be in 20 years.

Stackley had earlier said the procurement delay for the new Ohio-class submarine still left money for research and development.

“We’ve got to take advantage of the additional time to work on [the submarine’s] technology development, design maturity, retiring risk, so when the time comes [that] we award that boat, we are staring at a much more mature, more complete design so we can execute on schedule.”

That remark reflects problems he has dealt with on complex weapons systems. They are systems such as the new carrier, which has nearly a $1 billion overrun because the Navy tried to include many advanced elements that still are under development or not fully tested.

Stackley and Blake took legislators to school, but who knows how good what kind of students they’ll be on the challenges of the multi-dimensional, multibillion-dollar process of shipbuilding.

For previous Fine Print columns, go to washingtonpost.com/fedpage.