Department of Homeland Security Kirstjen Nielsen refused to apologize Monday for enforcing a policy that’s separated nearly 2,000 minors from their parents at the United States border and prompted comparisons to World War II-era internment of Japanese-Americans.

“This department will no longer stand by as law enforcement is attacked for enforcing laws passed by Congress,” Nielsen told the National Sheriffs Association on Monday, while speaking at the group’s annual conference. “We will not apologize.”

Her comments come just one day after Nielsen tweeted about the Trump administration’s practice of splitting apart families who cross the border without authorization, attacking the media for “irresponsible and unproductive” reporting and claiming that the administration has no such policy.

But rather than shedding light on the situation, Nielsen just confused everybody more (and made some statements that, while not false, were certainly misleading). This is what you need to know about why, and how, immigrants’ families are being torn apart.

What is the Trump administration’s stance on “family separation”?

Technically, Nielsen’s right. There is no official policy that officials must separate families who cross the border without authorization. But she’s also sidestepping a crucial fact: Families are still being split apart thanks to a Trump administration policy. And administration officials are doing that on purpose.

In May, Attorney General Jeff Sessions announced that the Trump administration would prosecute everybody who crossed the border without authorization. He framed the policy as a deterrent, meant to stop people from wanting to cross the border in the first place.

“If you smuggle an illegal alien across the border, then we’ll prosecute you for smuggling,” Sessions told a conference for the Association of State Criminal Investigative Agencies. “If you’re smuggling a child, then we’re going to prosecute you. And that child will be separated from you, probably, as required by law. If you don’t want your child to be separated, then don’t bring ‘em across the border illegally. It’s not our fault if somebody does that.”

In the past, people arrested after crossing the border were put into immigration detention, which can house kids. But now, under Sessions’ “zero-tolerance policy,” people facing criminal prosecutions are sent to federal jail. Those facilities don’t house kids.

That leaves parents with no choice but to be separated from their kids and sent to jail, where they may wait for weeks for a trial.

So what about seeking asylum?

Nielsen made sure to stress that people can still arrive at the border and ask for asylum, tweeting, “For those seeking asylum at ports of entry, we have continued the policy from previous Administrations and will only separate if the child is in danger, there is no custodial relationship between 'family' members, or if the adult has broken a law.”

But this tweet also ignores reports that people are physically unable to ask for asylum at points of entry. The Los Angeles Times reported last week that U.S. Customs officials refused to allow anybody to legally cross over a bridge from Mexico into the United States for nine days, since the officials were too overworked to process anybody. Almost 50 people, including children, were reportedly left wallowing for days in 100-degree-plus heat.

What is President Trump saying?

Ironically, Nielsen’s boss has contradicted her claim that there is no family separation policy. Trump has not only acknowledged the “forced family breakup at the Border,” he also blamed Democrats for it causing it. On Saturday, he tweeted, “Democrats can fix their forced family breakup at the Border by working with Republicans on new legislation, for a change!”

Trump’s claim is, quite simply, false. Democrats are not responsible for the zero-tolerance policy.

What’s everybody else saying?

Democrats, unsurprisingly, are roundly condemning the Trump administration’s practice of separating families at the border. But some more unexpected figures have also weighed in.

On Sunday, former First Lady Laura Bush wrote an op-ed for the Washington Post denouncing the policy as “cruel” and “immoral.” Bush, a Republican and Texan, likened the practice to interning Japanese-Americans during World War II.

“It is our obligation to reunite these detained children with their parents — and to stop separating parents and children in the first place,” she wrote. “People on all sides agree that our immigration system isn’t working, but the injustice of zero tolerance is not the answer.”

Even First Lady Melania Trump, who’s typically silent when it comes to her husband’s politics. Her communications director, Stephanie Grisham, told CNN on Sunday, "Mrs. Trump hates to see children separated from their families and hopes both sides of the aisle can finally come together to achieve successful immigration reform. She believes we need to be a country that follows all laws, but also a country that governs with heart."

How many children are being separated from their parents? Where are they being held?

Nearly 2,000 children were separated from their parents between April 19 and May 31, the Associated Press reported Saturday. In total, 1,995 minors were taken from 1,940 adults.

These children are classified as “unaccompanied alien children,” a term that’s usually used to describe minors who arrive in the United States without their parents. These kids are also handed off to a once-obscure agency in the Department of Health and Human Services, the Office of Refugee Resettlement. Some 10,000 children are now in shelters operated by ORR, according to NPR.

As of Friday, about 100 kids were also reportedly sent to a so-called “tent city,” composed of temporary shelters, in El Paso, Texas, the Texas Tribune reported. The temperature in El Paso is expected to climb above 100 degrees this week.