President John F. Kennedy chats with a group of leaders in the Bay of Pigs invasion on Dec. 27, 1962.William J. Smith / AP

Coming every four to eight years, the transition of power between presidents represents the most acute period of vulnerability for the United States. From the moment a new president takes the oath of office, the incoming administration assumes responsibility for national security—the area of U.S. policy in which the executive branch has the widest authority. Only the president can send American men and women into battle, authorize covert operations, or, under the most extreme circumstances, approve the use of nuclear weapons.

Preparing to become commander-in-chief is, therefore, a paramount priority for any president-elect during the 73-day period between Election Day and Inauguration Day on January 20. To facilitate that herculean task, the president-elect is authorized to receive intelligence briefings, including the President’s Daily Brief, an intelligence digest currently provided to President Barack Obama every morning. The president-elect can also learn about the United States’s “deep secrets”—including ongoing covert operations, the most sensitive intelligence-collection efforts, and even the procedures for nuclear launch.

Yet President-elect Donald Trump has not prioritized intelligence briefings since winning the election—and, indeed, it is unclear how many briefings he has received. Last week, news reports indicated that the total number was three—and Trump’s indifference to classified briefings was seemingly validated by his former campaign manager Kellyanne Conway, who said Trump is “receiving information through his personal and on-the-phone meetings with ... world leaders, in addition to meeting with 60 men and women who could serve in his government.” Yet, in the wake of intense controversy over Trump’s call with Taiwan President Tsai Ing-wen on Friday, Trump’s Chief of Staff-designate Reince Priebus contended: “He’s getting briefed. And it feels like every day. I’m not sure if it is every day. But it’s a lot.”

While Priebus’s comments may signal a step in the right direction, his statement does not allay fundamental concerns about Trump’s commitment to taking all the steps necessary to ensure national-security continuity when he takes office on January 20. The risks of neglecting the intelligence aspect of preparation for the presidency are grave. History shows numerous examples of failed crisis management during presidential transitions.

Most famously, in April 1961, President John F. Kennedy launched the Bay of Pigs invasion to overthrow Fidel Castro—a covert operation that failed, causing significant embarrassment to the United States, as well as the death or capture of nearly 1,300 CIA-trained anti-Castro fighters. The roots of this failure lay in inadequate intelligence briefings during the transition between President Dwight D. Eisenhower and Kennedy. Eisenhower initiated the covert CIA-led operation that would eventually become the Bay of Pigs invasion in 1959, and planning continued through 1960. Even after Kennedy defeated Richard Nixon, Eisenhower’s vice president, Eisenhower continued—and even accelerated—planning for a paramilitary operation to overthrow Castro.

During the transition period, Kennedy learned of the sketches of the Bay of Pigs scheme from his intelligence briefers. But the details continued to evolve through November, December, and January, and a scheduling snafu delayed and ultimately abbreviated Kennedy’s briefing on the operational details of the Bay of Pigs plan.  

As a result, Kennedy inherited a covert operation with substantial momentum behind it. Yet, as of Inauguration Day, he had not received a full briefing on the emerging Cuban operation and had an incomplete understanding of its history and details. Even so, Kennedy had to quickly decide whether to green-light the plan, as the CIA required executive authorization to continue with its program. Kennedy had to make this determination with little help from his foreign-policy advisers, who were not cleared to learn about covert programs until after Inauguration Day. Thus when Kennedy made the pivotal decision to authorize and accelerate planning for the Bay of Pigs operation eight days after taking office, he did so under tremendous pressure to continue an ongoing operation, with insufficient understanding of the plan itself, and with little support from aides.   

The results, of course, were ultimately disastrous.  

As the Bay of Pigs fiasco illustrates, the United States’ most sensitive national-security operations cannot be put on hold to accommodate the domestic-political calendar. Indeed, the Bay of Pigs is not the only example of early-term foreign policy crises and embarrassments resulting from the failure to share intelligence between administrations during the transition period.

President Jimmy Carter learned about secret payments to King Hussein of Jordan—millions of dollars over 20 years, paid in exchange for cooperation with American intelligence agencies—from a Washington Post investigation. Carter was understandably “distressed” that neither then-President Gerald Ford, Secretary of State Henry Kissinger, nor CIA Director George Bush had disclosed the program during the transition, and quickly stopped the payments.

Four years later, knowledge of Israel’s intent to strike the Osirak nuclear reactor in Iraq was lost in the transition from Carter to Ronald Reagan. Within days of the strike in June 1981, Reagan wrote in his diary: “We have just learned that Israel & the previous Admin. did communicate about Iraq & the nuclear threat & the U.S. agreed it was a threat. There was never a mention of this to us by the outgoing admin. [U.S. Ambassador to Israel Samuel] Lewis cabled word to us after the Israeli attack on Iraq & now we find there was a stack of cables & memos tucked away in St. Dept. files.”

And, on his first international trip to Mexico, President George W. Bush and his senior advisers were blindsided by the scope of “holdover” airstrikes against Iraq, conducted according to standard operating procedures established by Bill Clinton’s administration. Though nominally a routine operation to enforce the United Nations no-fly zones established after the First Gulf War, these strikes constituted the most extensive bombing in two years and hit 20 targets, including radars just outside Baghdad. According to Bob Woodward: “For a brief moment it had looked like the new Bush administration had launched a war against Saddam Hussein in its first month.”

These types of incidents can only be avoided through intelligence cooperation during the transition period. Obama has repeatedly offered to do everything in his power to facilitate a smooth transfer of power—but sharing intelligence, especially of the most sensitive national secrets, requires that President-elect Trump be a willing recipient.

In the weeks to come, the president-elect would do well to heed the warning of Eisenhower, his favorite president: “[An] emergency, arising at home or abroad during the first twenty four hours after a new President takes his oath of office, would demand decisions and actions which by reason of the unfamiliarity of new officials with their duties and authority, might result in bewilderment and lack of intelligent reaction, with resultant damage to the United States.” Accepting daily intelligence briefings is one obvious way Trump might avoid, or at least mitigate, such damage.

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