President Trump, how is this immigrant a danger?

President Donald Trump suggests that the aim of his crackdown on immigrants is to “defend Americans” from “savage,” “worst of the worst” intruders who kill Americans or at least are “dangerous criminals.”

What does Trump’s crackdown look like in real life? In Lawrence, Kansas, the other day, immigration agents handcuffed a beloved chemistry professor as he was leaving his home to drive his daughter to school. Then they warned his crying wife and children, ages 7 to 14, that they could be arrested if they tried to hug him goodbye, and drove off with him — leaving a shattered family.

Syed A. Jamal, 55, had been in America for 30 years, having arrived legally from Bangladesh as a student, before overstaying his visa. He loved Kansas and settled in Lawrence, teaching at colleges and volunteering at local schools. He coached students in science and sports.

Jamal, who seems just about the least dangerous person in America, is now in jail pending deportation to Bangladesh. A court intervened with a temporary stay as the government was trying to rush him out of the country.

While this arrest has done nothing to make anyone safer, it is devastating for three U.S. citizens — his children. Jamal is the only source of income.

If Jamal is indeed deported, his family will be upended. Randy Capps of the Migration Policy Institute estimates that 25,000 people deported in 2016 have children who are U.S. citizens.

Researchers have found that such children often bounce around among relatives, suffer in school and display self-destructive behaviors, such as cutting themselves.

A GoFundMe campaign has raised more than $39,000 for legal and other expenses.

Jamal earned a graduate degree in pharmaceutical sciences, worked as a researcher in cancer and genetics and became renowned for helping others. He even assisted elderly neighbors with their weekly shopping.

“The truth is, the country needs more neighbors like Syed,” wrote a local pastor, Eleanor McCormick.

Several years ago, immigration authorities ruled that Jamal had overstayed his visa, but the Obama administration exercised discretion, and he was allowed to stay if he reported in regularly. So Jamal had a temporary work permit and checked in with immigration authorities, most recently on Jan. 7. Everything seemed to be fine — until the immigration officers decided to blow up his family’s life.

The U.S. immigration system is a mess, and I don’t pretend there are easy solutions. But I don’t think we should lightly deport people who may have violated immigration rules but pose no threat and are embedded in American society — people like, well, Melania Trump, who worked without authorization on her visitor visa when she first came to the U.S., according to an investigation by The Associated Press.

I do believe it’s important to hold individuals to account for misconduct. So I tried to ask Homeland Security Secretary Kirstjen Nielsen why she is determined to destroy the lives of the Americans in the Jamal family. She did not respond, perhaps because she was too busy being a good citizen helping elderly neighbors with their groceries. Or maybe just deporting “savage” immigrants to protect Americans.