The U.S. Navy’s long-term shipbuilding plans — normally of little interest outside the Pentagon and beltway — have taken national center stage.

Republican presidential hopeful Mitt Romney put the Navy’s fleet plans front and center this week in the final presidential debate by saying the nation would drop to a 285-vessel force.

The assertion has forced Navy public affairs officials to address the service shipbuilding plan publicly in a way they never had before.

Perhaps the most reliable source of Navy ship numbers is the politically neutral Congressional Research Service, which on Oct. 18 released its updated shipbuilding and force report.

The report shows that, as with many things in such a debate, the subject may not be as black and white as presented.

The fleet numbers cited in the report range from a high of as many as 307 ships for fiscal years in the late 2030s and early 2040s to a low of 276 ships in fiscal 2015. There are 285 ships projected for a handful of fiscal years, including 2013. For most of the other years, the number hovers just below or above 300 ships.

“In February 2006, the Navy presented to Congress a goal of achieving and maintaining a fleet of 313 ships, consisting of certain types and quantities of ships,” CRS notes.

“On March 28, 2012, the Department of Defense (DOD) submitted to Congress an FY2013 30-year (FY2013-FY2042) shipbuilding plan that includes a new goal for a fleet of about 310-316 ships.”

CRS also points out that the Navy is conducting a force structure assessment, to be completed later this year, which could lead to a refinement of the 310-316-ship plan.

However, CRS reports, “The Navy’s FY2013 30-year (FY2013-FY2042) shipbuilding plan, which was submitted to Congress on March 28, 2012 (more than a month after the submission of the FY2013 budget on February 13, 2012), does not include enough ships to fully support all elements of the Navy’s 310-316 ship goal over the long run.

The Navy projects that the fleet would remain below 310 ships during the entire 30-year period, and experience shortfalls at various points in ballistic missile submarines, cruisers-destroyers, attack submarines, and amphibious ships.”

The projected cruiser-destroyer and attack submarine shortfalls are smaller than they were projected to be under the FY2012 30-year (FY2012-FY2041) shipbuilding plan, CRS says, due in part to a reduction in the cruiser-destroyer force-level goal and the insertion of additional destroyers and attack submarines into the FY2013 30-year plan.