Gen. Charles de Gaulle, a French hero and statesman who did not lack for self-esteem, once stated, “When I want to know what France thinks, I ask myself.” In October 1962, after U.S. charges that the Soviets had installed offensive nuclear missiles in Cuba — just 90 miles from the American mainland — the United States and the Soviet Union teetered on the dangerous brink of World War III. President John F. Kennedy sent former Secretary of State Dean Acheson to share America’s secret intelligence with French President de Gaulle and to secure France’s support.

After the private briefing, Acheson told the French leader that Kennedy had personally authorized him to show the general the then-top-secret surveillance photographs the White House possessed. But de Gaulle waved off Acheson’s offer: ”No, no, no, no. The word of the president of the United States is good enough for me.”

Nearly three decades later, in August 1990, after Iraq’s Saddam Hussein had invaded Kuwait, President George H.W. Bush and his secretary of state, Jim Baker, began the tricky and time-consuming hard work of putting together an international coalition of nations to pressure Iraq to withdraw from Kuwait.

Bush — largely because of the personal relationships he had established with world leaders as ambassador to the United Nations, as ambassador to China and as an eight-year vice president — was able to win backing for action from the U.N. Security Council, which included the Soviet Union. The team of Bush and Baker was able to enlist a remarkable coalition of troops from 32 nations — including France, Great Britain, Egypt, Syria, Sweden, Australia and Morocco — and to persuade Germany, Japan and Kuwait to foot most of the bill for the military operations that drove Saddam’s army out of Kuwait.

That was then, and this is now. Last year, we heard reckless and baseless comments from some celebrity developer/reality show host that, for example, the first African-American president of the United States is not an American, that the U.S.’ ”real unemployment rate is anywhere from 18 to 20 percent” and that in 2002 he had been ”totally against the war in Iraq,” but now reckless and baseless comments are coming from the most powerful man in the world.

Forget about the stupid charge that the Hillary Clinton campaign diabolically and brilliantly schemed to win the votes of 3 million to 5 million people voting illegally on Nov. 8 but failed to obtain a mere 75,000 votes in only three states — Michigan, Pennsylvania and Wisconsin — to win the presidency. Donald Trump, our 45th president — with no evidence, no witnesses and less credibility — accuses Barack Obama, our 44th president, of personally breaking the law and wiretapping him.

Beyond raising profound doubts about Trump’s fitness to handle the responsibilities of his office, this latest chapter reminds us that a president’s maturity, judgment and character do matter. When that inevitable global crisis does arrive and the United States seeks the crucial backing of the leaders of other nations, does anyone believe that a major leader, echoing the words of Charles de Gaulle in the Cuban missile crisis, will assure us that ”the word of the president of the United States is good enough”?