Over the course of my career, I’ve seen many presidential speeches. Some have been soaring and inspiring in their rhetoric, while others have been mediocre and disappointing. But none were like President Trump’s last Tuesday.

His address to the United Nations General Assembly was likely the most dangerous and alarming speech an American leader has ever given to a major international body. It was a national embarrassment — but more than that it was an urgent call to action for all of us who care deeply about world peace, peace in the Middle East and the security of the US and Israel.

To put this speech into historical context, I went back and reviewed past addresses by US presidents to the United Nations. Even at the height of the Cold War, when they were involved in bloody military conflicts, our leaders always urged restraint, negotiation and expressed a fervent wish for peace with our most bitter adversaries.

They spoke in mature, measured tones and appealed to our higher nature. Even if they made decisions that are now viewed as grave mistakes, they came across as leaders who took their awesome responsibilities seriously — and who understood how their words and actions could impact the peace and stability of the world.

President Eisenhower called for nations to “subordinate selfish interest to the general well-being of the international community.” President Kennedy said the United States had a “threefold responsibility — a responsibility to our own citizens; a responsibility to the people of the whole world who are affected by our decisions and to the next generation of humanity.” President Lyndon Johnson declared that “If there is one commitment more than any other that I would like to leave with you today, it is my unswerving commitment to the keeping and to the strengthening of the peace.”

Compare that to Trump’s childish branding of the leader of North Korea as “Rocket Man” and his reckless threat to “totally destroy” North Korea, a nation of 25 million people. Coming on the heels of his defense of white supremacists and neo-Nazis in Charlottesville, the president’s speech embodied an ugly brand of selfish militant nationalism, rather than the idea that all of the international community must work together for the common good.

The most relevant and concerning portion of the speech for J Street was the president’s indication that he was prepared to begin the process of tearing up the Iran nuclear agreement — probably starting on or just before October 15th, when he may decline to certify Iranian compliance with the terms of the deal. This would fly in the face of the overwhelming consensus of expert assessments and the insistences of all other signatories to the agreement. Congress could then introduce legislation to reimpose the sanctions lifted as part of the 2015 agreement.

If those sanctions are reimposed, the US will have reneged on our commitment under the agreement. We’d be left isolated among even our closest European allies — and would find ourselves on a path that could eventually lead to another disastrous conflict in the unstable Middle East.

Almost as dismaying as Trump’s speech was Prime Minister Netanyahu’s endorsement of it. Speaking just a few hours later, he went out of his way to praise Trump while repeating his own arguments against the Iran deal. In doing so, Netanyahu was flagrantly disregarding the advice he has received from the overwhelming majority of the Israeli security establishment, which says that the deal is working and has made Israel safer.

When it comes to the urgent, existential question of the Israeli-Palestinian conflict, Netanyahu brushed it aside in just a few sentences. This week, he is attending a massive state-sponsored rally to celebrate 50 years of settlement-building in the occupied West Bank — just the latest indicator of how far right he and his government have become. Meanwhile, Palestinian President Abbas urgently called for a renewed, serious effort to revive the two-state solution, although he again indulged in inflammatory rhetoric and one-sided accusations against Israel.

So what can we do when faced with an American president who seems determined to tear up the Iran deal, and an Israeli prime minister who has appointed himself Trump’s number one cheerleader?

We must mobilize all of our resources to ensure that the voice of opposition to these moves is overwhelming. Unlike in 2003, when President Bush’s drive for war with Iraq was strengthened by the support of some Democrats, Trump must be faced by a united and determined opposition. We must do our part to help educate and mobilize for this fight — in Congress, among US and Israeli policy experts and in our communities across the country. We must reach out to any and all allies who are willing to put national security and global stability over ideology and partisanship.

All this will require your voice, your work and your continued commitment. The stakes could not be higher.

No matter what he says, President Trump is not impervious to political pressure — and neither are members of Congress. They need to know that if they act to kill the nuclear agreement, they will bear responsibility for the disastrous consequences that could follow. The more that they understand the depth and breadth of opposition to this incredibly dangerous and foolhardy Iran policy, the more likely they are to act responsibly.

Of course, there are no guarantees. But this issue is so important that we owe it to ourselves, our nation, Israel and the world to not hesitate in this fight.

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