KITTERY – The Portsmouth Naval Shipyard basked this spring in the glow of a Navy Meritorious Unit Commendation that praised workers at the 205-year-old base for their “phenomenal record” repairing nuclear attack submarines.

A day later, the pendulum swung the other way, and cruelly. The Pentagon ticketed the shipyard for closing as part of a sweeping reorganization of military bases.

“They pulled the rug from under us,” Town Manager Jonathan Carter said bitterly. “To say we don’t need you anymore is a real blow to the worker, the community and the region.”

He’s not the only one feeling betrayed. The Pentagon has proposed shutting 33 large bases and scores of smaller ones across the country to save $48 billion over 20 years.

The burden would fall heavily on this coastal city along the New Hampshire border and the rest of Navy-dependent New England. Pentagon estimates show the overall region would absorb about half the net job losses – about 14,000 – on bases.

Most of the New England jobs would be lost by the closure of the Portsmouth shipyard and the submarine base in Groton, Conn.

At Groton, the majority of lost jobs – roughly 7,000 – would result from the transfer of military personnel. But in Portsmouth, civilians working on the base would take the hardest hit. About 4,000 would lose their jobs.

“Not only do you lose business but you lose friends,” says Chris Bistany, 35, taking orders for submarines – the edible kind – at Moe’s Italian Sandwiches in Portsmouth, N.H.

The Cold War over, Defense Secretary Donald H. Rumsfeld says the reorganization will help reposition the military for current threats and transform the armed services into a modern fighting force as the nation battles terrorists.

Bases once deemed essential now are considered obsolete by the Pentagon. But to affected communities, the bases remain economic engines and historic cornerstones – and losing them could be devastating.

“This has always been a military city. It’s who we are,” said Evelyn Marconi, a pipefitter’s helper at the Portsmouth shipyard during World War II who now runs a tight ship at Geno’s Chowder and Sandwich Shop.

Since 1800, the nearly 300-acre shipyard has sat along the New England coastline on an island in the Piscataqua River that separates the small town of Kittery, Maine, from the tourist enclave of Portsmouth, N.H.

The shipyard’s storied maritime and military milestones fuel pride on both sides of the river. In 1917, it was the site of the first submarine built in a U.S. naval shipyard. During its prime in World War II, the shipyard’s work force – mostly civilians – rose to more than 20,000 as submarines were built by the dozens.

In the 1970s, the base turned to repairing, refueling and overhauling nuclear-powered attack submarines. The Navy has scaled back that fleet from a Cold War peak of 98 to 54 today – and it is continuing to shrink.

The Pentagon says it no longer needs four bases where ships are repaired and refueled. It says shuttering Portsmouth will save $21 million initially, then $129 million annually by shifting work to yards at Norfolk, Va., Pearl Harbor, Hawaii, and Puget Sound, Wash.

Critics of closing Portsmouth question the Pentagon’s projected savings. They argue that the base fixes submarines faster than the other shipyards, saving the military tens of millions of dollars per ship.

So it was no surprise when four members of the base closing commission, which can change the Pentagon’s list of proposed closures before President Bush and Congress finalize them, were greeted by thousands of workers and townspeople last week when they visited the base.

The crowd stood five deep along the road, wearing “Save Our Shipyard” T-shirts, chanting “Take us off the list” and waving signs reading “On time, under budget, quality work.”

“We have a community where the people truly embrace this place,” said William McDonough, the shipyard’s commander in the 1970s who is leading an effort to spare it.

Congressional delegations from Maine and New Hampshire also are taking high-profile roles, hoping that if the commission doesn’t save the base, the president will when the list goes to him this fall. All four U.S. senators from the two states are Republicans. One – Olympia Snowe of Maine – faces re-election next year.

Presidential politics may well intrude. New Hampshire holds the nation’s first primary in 2008 and already state officials have prodded potential White House candidates – including Sens. Hillary Rodham Clinton, D-N.Y., and John McCain, R-Ariz. – to pledge their support for the shipyard.