Antiwar groups and other liberal activists are increasingly concerned at signs that Barack Obama’s national security team will be dominated by appointees who favored the Iraq invasion and hold hawkish views on other important foreign policy issues.

The activists are uneasy not only about signs that both Sen. Hillary Rodham Clinton (D-N.Y.) and Defense Secretary Robert M. Gates could be in the Obama Cabinet, but at reports suggesting that several other short-list candidates for top security posts backed the decision to go to war.

The activists — key members of the coalition that propelled Obama to the White House — fear he is drifting from the antiwar moorings of his once-longshot presidential candidacy. Obama has eased the rigid timetable he had set for withdrawing troops from Iraq, and he appears to be leaning toward the center in his candidates to fill key national security posts.

Kevin Martin, executive director of the group Peace Action, said that although Obama had campaigned as an agent of change, the president-elect is “a fairly centrist guy” who appears to be choosing from the Democratic foreign policy establishment — “and nobody from outside it.”

“So, in the short term, we’re going to be disappointed,” he said. “They may turn out to be all pro-war, or at least people who were pro-war in the beginning.”

Martin said that his group was concerned about Gates and Clinton as well as Rahm Emanuel, Obama’s choice for White House chief of staff. He also said his group was trying to mobilize its grass-roots supporters with e-mail alerts, but recognized that it must approach the subject delicately because of public euphoria over Obama’s historic victory.