President Trump with Japanese Prime Minister Shinzo Abe in Yokosuka, Japan, on Tuesday. (Charly Triballeau/EPA-EFE/Shutterstock)
Contributing columnist

Thankfully, the Cold War is over, and has little chance of returning: Neither Russia nor China will ever challenge us in the way the Soviet Union did. Yet our confrontation with an ideological and strategic superpower did produce some useful practices in the art of American diplomacy — norms that President Trump violated during his trip to Japan this week. It’s time we recall why our leaders once followed certain unspoken rules during the Cold War — and to consider re-adopting those same standards of behavior.

First and most importantly, U.S. presidents — be they Democrats or Republicans — never expressed personal approval of our communist adversaries. They never talked about Communist Party leaders as friends. They never “fell in love” with Leonid Brezhnev or Nikita Khrushchev. Of course, U.S. presidents engaged directly with their Soviet counterparts in the pursuit of U.S. national interests. But they did so without personalizing these ties and without excusing dictatorship.

Trump has practiced the opposite policy. During his visit to Japan this week, Trump again expressed affection for Kim Jong Un, tweeting about his “confidence” in the North Korean leader. Perhaps Trump’s personalized praise of autocratic adversaries will one day produce tangible outcomes for U.S. security and economic interests. So far, it has not.

Second, U.S. presidents engaged not only with governments of our enemies, but also sought to appeal directly to the people who live under these autocratic regimes, including especially Soviet citizens. This dual-track diplomacy was animated by the belief that those living in captive nations deserved our moral support even when we engaged with their oppressors on issues like arms control or trade. President Ronald Reagan and his administration were particularly effective in signaling to Soviet leaders that they were not going to check their values at the door in government-to-government negotiating sessions. But Reagan was not alone in this practice. Even Richard M. Nixon spoke directly to the Soviet people to explain our intentions.

To date, Trump has demonstrated very little interest in connecting with the oppressed peoples of North Korea, Russia, Saudi Arabia, Egypt or even Iran. (The only possible exception: Venezuela.) By the third year of his presidency, President Barack Obama already had met with hundreds — maybe thousands — of Russian students, entrepreneurs, civil society activists, journalists, and opposition leaders, both in Moscow and Washington. He even played basketball at the outdoor White House court with some Russian high-school players visiting Washington.

By contrast, to the best of my knowledge, Trump has had zero contact with Russian society. Even regarding Iran, Trump (perhaps inadvertently) offended many Iranians and Iranian Americans hostile to the dictatorship in Tehran when he vowed to bring about “the official end of Iran” in case of war. He ought to have threatened the Islamic Republic, its ruling mullahs or its theocracy, but he also ought to have expressed that the United States did not see the Iranian people as its enemy. Lower-level officials in the Trump administration made the distinction; Trump must do so as well.

Third, U.S. presidents and other politicians have embraced the practice of leaving our domestic squabbles at home when traveling abroad. They wanted to project a unified American voice beyond the borders of the country. In 1947, at the beginning of the Cold War, Republican Sen. Arthur Vandenberg (Mich.) delivered a stirring speech on the floor of the U.S. Senate that included the following remark: “We must stop partisan politics at the water’s edge.”

President Harry S. Truman echoed the phrase a year later while accepting his party’s nomination: “As I have said time and time again, foreign policy should be the policy of the whole Nation and not the policy of one party or the other. Partisanship should stop at the water’s edge.”

During the Cold War, especially during the Vietnam War, some U.S. politicians violated this norm. But the norm remained, nonetheless, and well past the end of the Cold War. While serving as the U.S. ambassador to the Russian Federation during the Obama administration, I saw admiringly how bipartisan congressional delegations spoke with one voice while meeting with Russian government officials, even if they sometimes fell back into factionalism behind closed doors. That commitment to our national interest — not Republican or Democratic interests — served our nation well.

That’s why Trump’s ridicule of a former two-term vice president while visiting Japan was so disheartening. Trump tweeted approvingly that Kim had “called Swampman Joe Biden a low IQ individual, & worse.” Any national leader writing such inflammatory comments about another U.S. public figure (and siding with a foreign adversary in the process) is unacceptable. The president of the United States flinging such insults at a former fellow White House official while in Japan is wrong. Doing so while also expressing affection for a North Korean murderer and dictator is disgusting.

We need a return to Cold War decorum in the conduct of presidential diplomacy. Leaders from the party of Reagan could take the lead in pressing for this return to thoughtful and ethical presidential conduct, especially while traveling abroad. If they don’t, then maybe voters in 2020 will be have to complete the task.

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