Mark Weinberg, a communications consultant, served as special assistant to the president and assistant press secretary in Ronald Reagan’s White House, is the author of “Movie Nights with the Reagans.”

Thirty-two years ago, Ronald Reagan gave what many believe was his most difficult and least favorite speech of his career. Some would say it was the most important.

Usually, when getting ready to address the nation in a prime-time Oval Office address, Reagan looked forward to it, or at least accepted the circumstances requiring him to do so. For example, he was energized to rally the nation behind his economic program, he was determined to call out the Soviet Union for its role in downing a commercial Korean jetliner, he wanted to comfort the country as we grieved the loss of the space shuttle Challenger, he was excited to announce his candidacy for reelection, and he was proud to review his administration’s record, while a bit sad to say goodbye, in his farewell address.

But things were different on the night of March 4, 1987, which, as it happened, was the Reagans’ 35th wedding anniversary. The long-awaited speech about the Iran-Contra affair — the illegal sale of U.S. arms to Iran and diversion of profits to the anti-communist Contras in Nicaragua — was no cause for joy. The White House was not a happy place. While many of us on the staff were relieved that the president would say what needed to be said, we knew it was not a speech he had ever anticipated having to give, nor was it one that he wanted to. But he knew he had to.

It turned out to be a watershed moment for the Reagan presidency. By uttering the words the nation had long waited to hear, Reagan was able to turn the corner on Iran-Contra.

It had taken a while for Reagan to get to that point. While he was shocked and disappointed when first told about Iran-Contra, he knew for sure that he had not directly or indirectly approved of what men he trusted had done. And he was somewhat reluctant to believe it. It was not until he received and read the report of the Tower Commission — the bipartisan group he appointed to examine what happened and make recommendations for future operations of the National Security Council — that he fully realized the magnitude of what had taken place and what he had to do. Once he did, there was no hesitation.

He was heavily involved in the writing of that speech. This is what he said:

I take full responsibility for my own actions and for those of my administration. As angry as I may be about activities undertaken without my knowledge, I am still accountable for those activities. As disappointed as I may be in some who served me, I’m still the one who must answer to the American people for this behavior. And as personally distasteful as I find secret bank accounts and diverted funds — well, as the Navy would say, this happened on my watch.”

What may have bothered Reagan most about the Iran-Contra affair was not what his rogue subordinates did — although he was mad about it — it was that polls showed the public did not believe him when he repeatedly said he was not aware of the scheme. He knew that without the people’s trust, he could not govern effectively, but even more than that, he just could not accept the fact that he was telling the truth but some people thought he was lying.

Contrast that, if you will, with the current president. It is widely accepted that Mr. Trump lies many times a day. As bad as that is, what’s worse is that he does not seem to care. Rarely if ever does he accept responsibility for his own mistakes or those of his subordinates. On the contrary, he always blames someone or something else for any failure. Nothing is ever his fault.

Equally obnoxious is how often he credits himself for things he did not accomplish. On his desk in the Oval Office, Reagan had a sign that said: “There is no limit to what a man can accomplish or where he can go if he does not mind who gets the credit.” Sadly, Trump has turned that principle of leadership — giving credit and taking responsibility — on its head.

For better orworse, Trump is who he is. We have no right to expect him to be Ronald Reagan. But telling the truth and accepting responsibility — even when unpleasant and unwelcome — are as basic as it gets when it comes to being a president with character and integrity, and we have every right to expect that of him.

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