The horrifying and heartbreaking news of the domestic terrorist attacks in El Paso, Texas, and Dayton, Ohio, in less than 24 hours over the weekend reached me while I was in Poland, a country haunted by the deadly power of politically irresponsible and racist rhetoric.

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I was participating in a series of events commemorating the 75th anniversary of the mass murder at Auschwitz-Birkenau death factory near Krakow, where in one night the Nazis killed more than 4,000 Roma and Sinti men, women and children, classified and persecuted by the Nazis as “Gypsies,” aliens, undocumented and other.

The motivation of the young white killer in Dayton is unclear.

But in El Paso, a 21-year-old white man apparently posted to social media a hate-filled, anti-immigrant rant before driving nine hours and 600 miles from the Dallas area to a Walmart, where you can see Mexico from the parking lot, to kill as many brown-skinned people as possible.

Wielding a semiautomatic, military-style rife — a weapon of mass destruction — the Texas shooter killed 20 people and wounded dozens more in a matter of minutes. The death toll in the El Paso shooting now stands at 22.

The scourge of homegrown racial terrorism is not new.

Since the birth of the Klan during Reconstruction, to the White Citizen’s councils of the ‘60s to Timothy McVeigh’s slaughter of 168 people, including 19 children, in Oklahoma City, the radical and racist right has used guns and bombs to intimidate and spread fear.

President Donald Trump said many of the right things at the White House Monday morning in condemning the shootings, racism, bigotry and white supremacy.

Better late than never. Now he must do the right thing. He can start by looking at the man in the mirror. He must end his use of racially charged (often racist) rhetoric and tweets for political gain. It is divisive, dangerous and diversionary.

I think he is better than that. I know the country is.

The president should also clean the swamp inside his administration.

During his campaign and in the White House — the people’s house — Trump has surrounded himself with racial ideologues, including his immigrant-bashing speech writer Stephen Miller, a close college friend of Richard Spencer, who, along with former KKK leader and Trump endorser, David Duke, were organizers of the demonstrations in Charlottesville where hundreds of neo-Nazis marched through the streets, chanting, “Jews will not replace us.”

Racism is a pathology. It is unscientific. It is immoral. It is a sickness. It is deadly.

The ideology of white supremacy is spewing hate, anti-immigrant and racially polarizing rhetoric. It is cannon fodder for these mass killings. These are not killings of passion, but political killings. Calling the shooters mentally ill is dismissing their plan of action, their ideology of supremacy and hate.

They are at war. They know what they’re doing and why.

We have a gun crisis, a hate crisis and a leadership crisis.

Trump must use his bully pulpit for something more than bullying. He must lead the way with action, not just words, in the passage of tough, meaningful gun control and an immediate ban on the military-style weapons used by both killers in El Paso and Dayton.

He must demand his fellow Republicans do the same. The House has passed gun legislation that would likely reduce such mass killings in the future, but Senate Majority Leader Mitch McConnell has refused to bring it before the Senate for a vote.

Mr. President, start twisting arms. These political acts of domestic terrorism are an attempt to undercut our democracy. The combination of well-armed white nationalists and white supremacists, and a multiracial democracy, cannot co-exist.

The president must take a moral stand for humanity and curb his ugly rhetoric.

His FBI must clamp down on right-wing, white nationalist groups inspiring and committing these acts of violence. He must join the American people who are demanding sensible gun safety measures.

Prayers and condolences are not enough.

We need action. We need gun control. We need the political will and moral leadership to stop the violence, save the children — and the country.

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