KITTERY – Surviving previous rounds of military base closings has put the Portsmouth Naval Shipyard in a strong position for the next one in 2005, a former commander says.

Capt. William McDonough, a leading advocate for the yard, said previous rounds of base closings cut the number of public naval shipyards in the country from eight to four.

Add to that Portsmouth’s deep-water harbor, its submarine dry docks and that only two private shipyards in the nation are licensed for certain work on nuclear-powered submarines, and Portsmouth has the start of a good case for staying in business, McDonough said.

“You can’t take nuclear submarines to any other place except a deep-water harbor,” he noted.

Critics have long said the country has too many military bases, partly because members of Congress fight closures in their districts. In response, Congress and the Pentagon now review bases nationwide using rules intended to promote fairness and objectivity.

In four rounds of closings – in 1988, 1991, 1993 and 1995 – the Pentagon picked 97 major domestic bases for closure, 55 major bases for realignment and 235 minor installations either to be closed or realigned.

Pease International Tradeport in Portsmouth was an Air Force base before it closed about a decade ago.

If Defense Secretary Donald H. Rumsfeld has his way, the 2005 round of closures will cut as deeply as the previous four rounds combined, a top aide said last month.

“All installations are on the table,” said Raymond DuBois, the deputy undersecretary of defense for installations and environment.

In each round, the defense secretary proposes bases for closure or realignment. A commission evaluates the list and submits its decisions to the president. Congress must approve or reject the president’s final list without making changes.

McDonough said the yard’s recent record of doing work on time and under budget will help it.

“It think we’re in a position to make some really good arguments,” he said.