William P. Clark Jr.

In the 1960s and 1970s, Clark held a series of public posts in state government. In September 1967, Clark became the Executive Secretary to Governor Ronald Reagan.[2][3] Clark was a judge of the Superior Court of California from 1969 to 1971, in Paso Robles, San Luis Obispo County.[4] On July 30, 1971, Governor Reagan elevated Clark to Associate Justice of the California Court of Appeal, Second District, Division One.[5] In January 1973, Governor Reagan appointed Clark as an Associate Justice of the California State Supreme Court, where he served from March 23, 1973, until February 25, 1981.[6][7][8]

In 1980, Ronald Reagan won the election as President of the United States. Clark reached the apex of his power when Reagan appointed Clark as National Security Advisor, and he temporarily became preeminent among presidential aides. A longtime rancher friend of Reagan, according to Edmund Morris's Dutch, Clark would walk into Reagan's office unannounced, an unheard-of practice for even the most senior officials. Clark even suggested to the president in light of foreign policy troubles bedeviling the United States in the mid-1980s that Reagan considers not running for reelection in 1984. By that time, however, George Shultz had surpassed Clark in influence, and Reagan apparently gave Clark's suggestion no thought.

Clark's biographers credit him with convincing Reagan that the Soviet Union could be pushed to the edge of collapse. The strategy was opposed by Secretary of State George Shultz, among others, leading to rancor in the White House.[9]

Morris writes in his admitted semi-fictionalized narrative biography that Clark resigned in late 1983 when he tired of the "unceasing hostility of [Michael] Deaver, George Shultz, and Nancy Reagan." Morris described Clark as "the only man who ever got within a furlong of intimacy" with the notoriously distant Reagan, and his ability to relate to Reagan inspired jealousy, at the same time that Clark's taciturn nature made him unlikely to build allies.

A differing PBS account[10] quotes Mike Deaver via his book "Nancy", pg. 48: "Staff might have resented my closeness with Nancy, but to my knowledge, it was never a problem. Bill Clark and Ed Meese, then the legal-affairs counsel, were happy to have me working closely with Nancy because that freed them up to concentrate on policy and appointments. Often, too they would use me as back door to the first lady, to get her input ..." The PBS "Role of a Lifetime" url also lists some support of a conflict with George Shultz: "I knew that I would have to insist on dealing directly with the president. I could not let the White House staff interpret me to him. That was especially true when it came to Clark, because his views and instincts were different from mine ..." Noted authority Lou Cannon concluded that "[Mrs. Reagan] was very much opposed to Bill Clark. She wanted him out of (the NSA position) because she felt that it was interfering with (President) Reagan's efforts to open up better relations with the Soviet Union." Fellow Reagan family biographer James Benze furthers in the commentary, "Nancy Reagan (then) enlists other moderates in the administration to make William Clark's life miserable as National Security Advisor."

On September 21, 1983, Secretary of the Interior James G. Watt embarrassed the administration by making bigoted remarks to the media, causing him to resign on November 8, and Clark requested and received an appointment to replace Watt.[11][12]

Clark with Defense Secretary Donald Rumsfeld in 2001

Clark returned to California after his stint serving the administration and pursued a variety of law firm and other business interests.[13]

After the Iran-Contra hearings in Congress, Clark wrote privately to Reagan urging him to pardon his three aides who were threatened with indictments in the conspiracy: Oliver North, John Poindexter, and Robert McFarlane.[14] Under President George H. W. Bush, Clark also orchestrated the lobbying campaign to obtain a pardon for his friend Caspar Weinberger.[15]

In July 2011, Clark became a member of the United States Energy Security Council,[16] which seeks to diminish oil's monopoly over the United States transportation sector and is sponsored by the Institute for the Analysis of Global Security.[17]

As National Security Advisor for Ronald Reagan, Clark frequently consulted with and visited with the three living former presidents, Richard Nixon, Jimmy Carter, and Gerald Ford, leaving a briefing book with them on subjects important to them. For Nixon, it was on East-West Relations including the Soviet Union; for Carter, the Middle East, and for Ford, domestic matters. Consulting with predecessors, in the White House and in the Cabinets of either party, was important to Clark's and therefore, Reagan's success. "While I did not always agree with (former National Security Adviser and Secretary of State) Henry Kissinger's views on national security, I had a close relationship with him and would take his call any time of the day or night," Clark said. "Recognizing that the Reagan administration was serving at the height of the Cold War, I would get his opinions as well as other predecessors in national security–at the Pentagon, State Department and, of course, the White House."

Clark was dismayed at the tones of early 21st-century politics in the United States. "There was a lack of contentiousness between the two political parties that I'm afraid does not exist today," Clark said. "That's one of my worries about making government work — there seems to be far less camaraderie now than we've known in the past."[18]

Clark retired to his ranch near the rural community of Shandon, California, where he built a small chapel in the hills of his ranch. On August 10, 2013, Clark died of complications from Parkinson's disease at his home in Shandon, at age 81.[19][20] He is interred at the Shandon Cemetery in Shandon, California.