FOLLOWING THE 2016 ELECTION, President Barack Obama rightly warned the Donald Trump transition team “we only have one president at a time.” It was a reminder that there can be one person articulating American foreign policy so world leaders will have no doubt as to the intentions of the United States.

Obama’s former Secretary of State John Kerry ignored that warning and has been behaving as if he’s still in office.

Kerry, wrote the Boston Globe, engaged in some unusual shadow diplomacy with Iran’s foreign minister, Mohammad Javad Zarif, at the United Nations in New York, reportedly to try and salvage the Iran nuclear deal they spent years negotiating. Tuesday, Trump followed through on his promise to end America’s participation in the deal. In response, Sen. Marco Rubio (R-Fla.) tweeted that it does not further U.S. national security, neither was it a binding agreement under U.S. law because it was never submitted for Senate approval. Rubio called it a political agreement by the previous administration.

Last week, in an apparent attempt to influence the president’s decision on re-certifying Iran’s compliance, Israeli Prime Minister Benjamin Netanyahu revealed a treasure trove of documents obtained by Mossad, Israel’s intelligence agency, which he said proves Iran has been cheating on the agreement. Apparently, this had no influence on Kerry.

This is why we have the Logan Act, which forbids private citizens from engaging in unauthorized correspondence with foreign governments that have any disputes or controversies with the United States. That includes direct or indirect correspondence, unauthorized meetings or discussions, any contact at all. Violation can result in a fine, up to three years in prison, or both.

Is Kerry an authorized person? No. Is Iran a foreign government? Yes. Does Iran have a dispute with the United States? It does. Has Kerry committed a criminal offense?

The Chairman of the House Permanent Select Committee on Intelligence, Rep. Devin Nunes (R-Calif.), has called for Kerry to be arrested for violating the Logan Act. That is as likely to happen as Hillary Clinton being locked up for what she did with her “irresponsible” handling of classified emails.

Kerry isn’t the first person to attempt to undermine the policies of an administration. In the early ’80s, Sen. Edward Kennedy (D-Mass.) sent a letter to the head of the KGB in what was regarded as an effort to counter President Ronald Reagan’s arms buildup and put the Soviet Union on the ash heap of history.

In a 1983 memo addressing the letter, sent by KGB head Viktor Chebrikov to then-Soviet General Secretary Yuri Andropov, Chebrikov explained that Kennedy was eager to counter the militaristic policies of Reagan.

Kennedy’s message was simple, wrote forbes.com. “Kennedy would lend Andropov a hand in dealing with Reagan. In return, the Soviet leader would lend the Democratic Party a hand in challenging Reagan in the 1984 presidential election. ‘The only real potential threats to Reagan are problems of war and peace, and Soviet-American relations,’ the memorandum stated. ‘These issues, according to the senator, will without a doubt become the most important of the election campaign.’

“Kennedy then offered to make it possible for Andropov to sit down for a few interviews on American television. ‘A direct appeal to the American people will attract a great deal of attention and interest in the country.’ If the proposal is recognized as worthy, then, Kennedy and his friends will bring about suitable steps to have representatives of the largest television companies in the United States of America contact Andropov for an invitation to Moscow, Russia, for the interviews.”

Fortunately, Reagan’s policy of peace through strength prevailed. Kennedy clearly was in violation of the Logan Act, yet paid no price for his meddling.

Congress should clarify the Logan Act. If people like Kerry and Kennedy can get away with their actions, is the law still relevant? Should it be? Yes, it is and yes, it should. Congress needs to answer these questions soon to prevent a recurrence of this dangerous practice.