Elie Wiesel is one of my greatest heroes and I’ve been lucky to have a warm friendship with him. I would rarely consider disagreeing with such a global moral giant and one of the foremost Jewish personalities of all time who has had such a profound impact on my life.

Except on one issue. Hate.

In many conversations, Wiesel (or as I call him, Reb Eliezer) has told me that I am wrong on the subject of hatred. We can’t hate even our enemies. It seeps into our blood stream and poisons us.

But what happens when it is not our enemies but the enemies of humanity itself, the enemies of all that is good, the nemesis of morality and life itself? What should we feel then?

But what are we supposed to feel for an organization like Hamas if not hate? How are we supposed to carry out our moral resolve to fight a genocidal organization sworn, like the Nazis, to the extermination of the Jewish people if we don’t detest and loathe them? How are we supposed to react to a terror organization that perpetrates honor killings against innocent Palestinians women, uses Arab children as shields for its missiles, and teaches Palestinian children that rather than living a long and productive life they are better off blowing themselves up?

Wiesel is one of the softest, most noble souls I have ever met, so I understand his reluctance to harbor any kind of hatred. And I can understand that saintly souls like him refuse to hate even wicked murderers.

But for the rest of us mortals, especially political leaders sworn to uphold the world order, I believe that the greatest moral failure of our time is a refusal to hate evil. Hatred of evil implies both the right to make judgments as well as a belief in moral absolutes, both of which are anathema to liberalism and modern sensibilities.

Abraham Lincoln famously said that he hated slavery, just as Churchill famously said that he hates Hitler.

Many today seek to understand, rather than resist, evil. They excuse the murderous actions of Hamas by speaking of Palestinian humiliation. They ask questions like, What motivates a Palestinian suicide bomber to detonate himself and murder children? Is it degradation at the hands of Israelis? Poverty perhaps? Can we find mitigating circumstances that might excuse their actions?

As I write these words the world is on fire almost everywhere. The news is almost universally awful. From Russian-destroyed airliners and bodies strewn over the Ukraine to the rise of blood-thirsty thugs like ISIS and Boko Haram, the world situation is dispiriting and depressing.

Presiding over all of it is the most powerful man in the world who seems to be checked out.

President Obama is a moral man with clear moral sensibilities. He speaks eloquently and he is super smart. But the pivotal shortcoming of his leadership and foreign policy is a failure to be reviled by evil. Evil doesn’t seem to sicken him to his stomach.

When he speaks about the worst kind of abuses he uses vague, technical language and avoids definitive moral terminology like calling Hamas or Boko Haram evil. Why the reluctance to make declarative statements of an absolute nature? Because moral ambiguity can justify inaction.

Iran has threatened a second holocaust on countless occasions. But last December the president had this to say about Iran: “The idea that Iran, given everything that we know about their history, would just continue to get more and more nervous about more sanctions and military threats and ultimately just say, ‘We give in,’ I think does not reflect an honest understanding of the Iranian people and the Iranian regime. I think even the so-called moderates or reformers inside of Iran would not be able to simply say, ‘We will cave and do exactly what the U.S. and the Israelis say.”

In the coolness and detachment of the President’s pragmatism toward Iran and the extension he has just offered them in the nuclear negotiations, you might think he was talking about a trade deal with Switzerland. You would not know that he was speaking about a regime that machine-gunned its own citizens in the streets when they protested a stolen election in 2009, stones women to death, and hangs homosexuals from public cranes. You would not know the President was speaking about a country whose government is the foremost funder of terrorism worldwide, with Hamas being one of their principal beneficiaries.

President Obama’s reluctance to use the word “terrorism” has been much discussed. In 2009 his administration formally retired the phrase “War on Terror” and replaced it with the evasive and euphemistic “Overseas Contingency Operations.”

It took him days to definitively describe last year’s massacre at the American embassy in Benghazi as a terrorist attack against the United States. The Washington Post writes that President Obama had spoken generally about “acts of terror” after Benghazi, but “he did not affirmatively state that the American ambassador died because of an “act of terror.””

The deadly terrorist attack at a Kenya mall this past September followed the same pattern. President Obama said, “We stand together with Kenya in our resolve to confront and defeat violent extremism.”

Perhaps this would explain John Kerry’s willingness to pressure Israel into a ceasefire with Hamas that would leave much of their terror infrastructure in place.

It’s absolutely horrible seeing Palestinian children dying in Gaza. But the President has to come out clearly and say he loathes the cowardly terrorists of Hamas who continue to use these children as their shields.

To be sure, President Obama and John Kerry are friends of Israel. I will not join the chorus of those who character-assassinate two men who have done much for Israel. So why is there a perception that their sympathies lie elsewhere? Because they don’t seem to get, and do not state definitively, that Israel is in a simple battle of good versus evil.

Hamas is evil incarnate. It is a menacing, death-glorifying, women-hating, gay-murdering, anti-Semitic death cult. It has no redeeming qualities.

I do not expect the President to agree with every word of this characterization. But I do expect him to use one word that encapsulates Hamas: evil.

President Reagan said in March 1983: “Let us be aware that while they [the Soviet leadership] preach the supremacy of the state, declare its omnipotence over individual man, and predict its eventual domination of all peoples on the earth, they are the focus of evil in the modern world.” He implored his audience not “to ignore the facts of history and the aggressive impulses of an evil empire… and thereby remove yourself from the struggle between right and wrong and good and evil.”

In the end, it was Martin Luther King who summed it up best: “He who passively accepts evil is as much involved in it as he who helps to perpetrate it. He who accepts evil without protesting against it is really cooperating with it.” Tolerating the intolerable and forgiving the unforgivable is the surest way to empower evil. And if Hamas is not evil, then the word has no meaning.

President Obama can salvage so much of his legacy on foreign policy by beginning to employ the language of moral absolutes, especially when it comes to terror organizations who target civilians.

Mr. President. The world is watching. History is taking note. Use your considerable eloquence to lead the world out of moral ambiguity.

Rabbi Shmuley Boteach, “America’s Rabbi” whom the Washington Post calls “the most famous Rabbi in America,” is the international best-selling author of 30 books, including The Fed-up Man of Faith: Challenging God in the Face of Tragedy and Suffering. Follow him on Twitter @RabbiShmuley.