WASHINGTON (AP) -- Onetime economics professor and longtime nuclear strategist James R. Schlesinger was a political man for all seasons, holding a long string of Cabinet and other high-level posts through three administrations. He was hired -- and dismissed -- by presidents of both parties.
Schlesinger, who died Thursday at the age of 85, built an impressive national-security resume under Republican presidents Richard Nixon and Gerald Ford and served as the nation's first energy secretary under Democratic President Jimmy Carter during the energy crisis of the late 1970s.
Earlier, he served as a White House budget official, chairman of the Atomic Energy Commission and director of the Central Intelligence Agency under Nixon; and as defense secretary under both Nixon and Ford.
Both Carter and Ford sent the scrappy, Harvard-educated Schlesinger packing after a few years. But he kept bouncing back. In later years, he served on a succession of defense and nuclear-energy related government advisory boards and panels.
Energy Secretary Ernest Moniz recalled his friendship with Schlesinger over the last 15 years and said their discussions on nuclear security and other issues always "led to new insight and perspective on issues of national significance. His counsel will be missed."
Moniz added: "We are still reaping the many benefits from his leadership of the department."
Schlesinger was "a remarkable public servant," former Sen. Sam Nunn, D-Ga., said. Nunn sparred often with him as chairman of the Senate Armed Services Committee. Sen. John McCain, an Arizona Republican who is a leading congressional voice on national defense, said Schlesinger "dedicated his life to protecting America's national security."
Schlesinger gained a reputation as a perceptive thinker on nuclear strategy, advocating a retreat from reliance on mutually assured destruction as a means of avoiding nuclear war with the Soviet Union. "Deterrence is not a substitute for defense," he said.
"He left an astounding mark on American security and energy policy," the Center for Strategic and International Studies, the Washington think tank where Schlesinger was a trustee, said on its website. "After leaving government, Dr. Schlesinger continued to promote a stronger and more prosperous country through his work at many policy institutions, including CSIS."
At the Pentagon, he worked to rebuild military morale and revamp nuclear strategy in the turbulent period after the Vietnam War.
Becoming defense secretary in 1973 at age 44, Schlesinger was well-liked among military leaders, consulting with them frequently and aggressively lobbying Congress for more money for the armed forces. His pro-interventionist foreign policy also brought him favor with the new-right coalition of the day.
But his bluntness and tenacity in military budget struggles made for often prickly relations with Congress and with Secretary of State Henry Kissinger. President Ford fired him in 1975 and replaced him with his White House chief of staff, Donald Rumsfeld.
"Schlesinger has been extremely ruthless and irritating," Kissinger confided to James Reston of The New York Times shortly thereafter. "I think the president just decided he had had enough."
But Schlesinger wasn't gone for long.
He was back in the senior ranks of government roughly two years later, serving first as Democrat Carter's energy "czar" and then as the first secretary of the new Energy Department, created amid severe fuel shortages and soaring prices spawned by Arab-world oil embargoes of the 1970s spawned by turmoil in the Middle East.
Schlesinger easily made the transition from national security posts to overseeing energy policy, seeing many similarities and supplying Carter with the phrase "moral equivalent of war" for describing the national energy emergency.
"The phrase became abused later on, was misunderstood," he later reflected. "The Wall Street Journal referred to it as MEOW and that caught on."
The pipe-smoking, sardonic Schlesinger sometimes exasperated his congressional critics, who viewed his frequent and often lengthy congressional testimony as lecturing. He drew criticism from Democratic and Republican lawmakers alike as he labored on the sidelines for months in nudging along Carter's multi-faceted energy program.
A House-Senate conference committee negotiating a natural gas pricing compromise proved particularly tedious to him. "I understand what hell is," Schlesinger said at one point. "Hell is endless and eternal sessions of the natural-gas conference."
But Carter, with Schlesinger's help, finally got most of his big energy program through Congress, including strict new conservation standards, a since-expired tax surcharge on "gas-guzzler" autos and gradual oil and natural gas price deregulation.
In 1979, Schlesinger was abruptly replaced by Carter as part of a broader Cabinet shakeup.
"I told Jim Schlesinger it was time for him to step down, since he had submitted his resignation on two previous occasions," Carter wrote in his White House diary. "I offered him a major diplomatic post, but he said he couldn't take seven children overseas. We parted company in a very friendly spirit."