Is it true that Jimmy Carter and Bill Clinton have an uneasy relationship?
I'm sure everything has mellowed over the years since Clinton left office, but they absolutely had a frosty relationship. They had issues dating back to when Clinton was Governor of Arkansas and Carter was still the incumbent President and they seemed to pick up where they left off once Clinton was in the White House.
In fact, there was tension between Carter and his four immediate successors (Reagan, Bush 41, Clinton, and Bush 43). While most former Presidents of the post-World War II era have largely avoided criticizing the incumbent Presidents, Carter was often very candid about certain policy or political issues after leaving office. Carter's work around the globe with the Carter Center was also sometimes seen as influencing or interfering with White House initiatives or events for several different Administrations.
As Jonathan Alter wrote in his excellent 2020 biography of Carter, His Very Best: Jimmy Carter, A Life (BOOK | KINDLE | AUDIO):
Carter traveled to more than 140 countries after leaving office -- returning to several of them more than a dozen times -- and he said he always kept the State Department apprised of his trips. But the notifications were often pro forma, as if he merely had to check a box before going off on his own.
It was no secret that Carter was not a member in good standing of the ex-Presidents' club, in part because he never accepted their code. The unwritten rules aren't complicated: former Presidents are expected to build their libraries and at least try to hold their tongues about the incumbent, not complain -- as Carter often did -- that the policy is wrong or they are underused by the President. No one sitting in the Oval Office likes the idea of a freelance Secretary of State. At the same time, five of the six Presidents who succeeded Carter (all except Reagan) recognized the usefulness of his vast knowledge and high-level contacts. The challenge for them was managing their high-maintenance predecessor.
When Carter was President, he took care to cultivate relationships with his living predecessors -- Richard Nixon and Gerald Ford -- and he welcomed their support on China, the Panama Canal, and other issues. After leaving office, he got along exceptionally well with Ford, who joined him on several post-Presidential projects. Ford and Carter promised that each would deliver the eulogy if the other died first. Ford did, and Carter remembered him warmly at his funeral in 2006. George H.W. Bush believed the Ford-Carter bond "set a wonderful example of cooperation and friendship" between old rivals.
Carter's successors were a different matter. He said he had "okay relations" with the Bushes -- especially George H.W. Bush -- and Donald Trump in his first two years. It was the Democratic Presidents, Clinton and Obama, whom he found "cooler and more aloof." No one who watched their interactions over the years would be left to wonder why.
Regarding that relationship between Carter and Clinton, Alter also wrote:
During the 1992 Presidential campaign, the tensions between Carter and Bill Clinton of a dozen years earlier resurfaced. "People are looking for somebody who is honest and tells the truth," Carter said in a remark that took on added meaning because it came amid the first national stories of Governor Clinton lying about sex. Clinton, for his part, worried that Carter's failures as President would rub off on another southern governor and hurt his chances.
After the election, Clinton wouldn't take Carter's calls. He finally handed him off to Warren Christopher, his transition director and choice for Secretary of State. "Chris" quickly grew tired of Carter, too, and fobbed him off on his undersecretary, Peter Tarnoff. Carter felt snubbed. Clinton's basic problem with Carter was that he too often crossed the line from expressing his views on a subject to saying the President "should" do something. Carter admitted later that while he didn't intend to be personally critical, "I may not always have succeeded."....
....As Carter moved around the world, the Clinton White House had no confidence that he would limit himself to his assigned mission without making concessions that the President never approved. The White House knew that Carter understood that recalling a former chief executive like some errant ambassador was difficult if not impossible, which meant that he could hog glory and operate outside the President's control. This happened twice in 1994 [in North Korea and Haiti], a year that was simultaneously the peak of Carter's success as a peacemaker and the nadir of his forty-year relationship with Clinton.