The United States’ ongoing war against Iran is causing American Jews’ already high levels of anxiety and dread to soar even further.

They have good reason for such fears.

Ever since the barbaric Oct. 7 attack on Israel and the Gaza war that followed, Jews in America, Britain and other western countries have been subjected to a tsunami of hatred.

Israel is the only country in the world being singled out for this incitement — and Jews outside Israel are the only people held collectively responsible for a country they don’t live in.

Jews in America and elsewhere have been poleaxed by the staggering normalization of antisemitic hatred and violence.

In everyday conversation, they are aghast to hear facts and evidence about Gaza or Iran simply batted aside by under-informed activists and acquaintances on both the left and the right, all schooled by the online outrage machine.

Worse still, Jews are being targeted for abuse as if they’re personally responsible for Israel’s alleged misconduct.

I’ve heard of cases in which close friends from childhood have suddenly cut off contact because of their anger over “Palestine.”

In Australia, a businesswoman told me she was in the middle of negotiating a contract when she was suddenly asked without preamble: “Why are you killing babies in Gaza?”

In New York City, a woman asked me, “What do I tell my granddaughter who says Israel is committing genocide?”

So while hardening their physical security must take top priority, Jews must as well take action to defend themselves on the battleground of the mind.

Otherwise, the indifference or hostility of the wider community will surely grow — and so will the danger to Jewish institutions and lives.

But how can any one individual respond to this ongoing effort to turn an entire faith community into social pariahs?

My new book, “Fighting the Hate: A Handbook for Jews Under Siege,” is a primer on how to confront this hideous onslaught.

The main lesson is this: Don’t get mad, get smart.

While some anti-Jewish tormentors are beyond reason, it’s possible to develop strategies that can flip the script and begin to open other minds — even by just a crack.

It starts when we stop playing defense when hit with claims of Israeli misdeeds.

Use such attacks as an opportunity to provide a nugget of information or a thought that tells your antagonist something surprising or interesting.

If someone says, for example, “You killed Palestinian children,” don’t protest that this is an obscene comment.

Instead, ask the other person if they agree it’s shocking that Hamas provided not one bomb shelter for civilians, while building hundreds of miles of underground tunnels solely for its own fighters’ use.

If someone says Israel is a white racist “ethnostate,” tell them that most Israelis are dark-skinned.

About 20% of citizens are Israeli Arabs, and a majority of Israeli Jews are brown or black, with origins in ancient Jewish communities in the Muslim world.

Use humor wherever possible: When confronted by inflated Gaza Health Ministry claims about war casualties — not one of whom is acknowledged to have been a terrorist, or to have died of old age or disease — merely praise Gaza for becoming the first society in the world to miraculously abolish natural death.

And in the bigger picture, more Jews need to speak up to defend the historic culture of America and the West, and to call out the liberal shibboleths that have so badly undermined that culture.

Today, Jews are at the sharp end of this onslaught — but all those seeking to defend Israel and America must also begin to make themselves heard.

The security of all Americans is in peril if we refuse to grasp the threats of Islamism at home and of Iran abroad.

My home country of Britain should stand as a warning.

The United Kingdom’s traditional freedoms and liberties have been all but lost amid its leaders’ supine appeasement of a politically powerful Muslim community.

That community has made steady progress toward its goal of Islamizing the country — just as Mayor Zohran Mamdani appears to be attempting in New York.

The Islamists are only able to make such inroads because of their all-too-willing accomplices on the left.

They are bound together by their shared goal of bringing down Western society — despite diametrically opposed views of what should replace it — and their mutual hatred of Jews and Israel.

We aren’t merely witnessing a rise in antisemitism, but a global madness that threatens the West as a whole.

Not just the Jews, but all who are desperate to defend civilization against barbarism need to fight back.

Melanie Phillips is the author of “Fighting the Hate: A Handbook for Jews Under Siege” (Wicked Son).