It was just a few months ago when Donald Trump presented a new idea about how he’ll attack Sen. Elizabeth Warren (D-Mass.), whose Native American ancestry has long been a point of preoccupation for the president. Imagining a 2020 debate, Trump told an audience of supporters about his future plan.

“I’m going to get one of those little [DNA testing] kits and in the middle of the debate, when she proclaims she’s of Indian heritage…,” Trump said. “And we will say, ‘I will give you a million dollars, paid for by Trump, to your favorite charity, if you take the test and it shows you’re an Indian.’ And we’ll see what she does. I have a feeling she will say no, but we will hold it for the debates.”

The president may need to track down his checkbook. The Boston Globe reported overnight:

Senator Elizabeth Warren has released a DNA test that provides “strong evidence” she had a Native American in her family tree dating back 6 to 10 generations, an unprecedented move by one of the top possible contenders for the 2020 Democratic nomination for president. Warren, whose claims to Native American blood have been mocked by President Trump and other Republicans, provided the test results to the Globe on Sunday in an effort to defuse questions about her ancestry that have persisted for years. She planned an elaborate rollout Monday of the results as she aimed for widespread attention.

As the Globe reported, the analysis was conducted by Stanford University’s Carlos Bustamante, a renowned scholar and expert in the field, who concluded that the results “strongly support the existence of an unadmixed Native American ancestor.”

The article added, “Bustamante calculated that Warren’s pure Native American ancestor appears in her family tree ‘in the range of 6-10 generations ago.’ That timing fits Warren’s family lore, passed down during her Oklahoma upbringing, that her great-great-great-grandmother, O.C. Sarah Smith, was at least partially Native American.”

In other words, Trump assumed Warren was lying about her ethnicity. She wasn’t.

All of this is notable for a few reasons.

First, the president’s interest in the senator’s family background has at times been a little creepy. As recently as last week, Trump said at a rally in Iowa that he’s eager to “finally get down to the fact as to whether or not she has Indian blood.” I’ll resist the urge to speculate as to why he considered this so important, but whatever the rationale, the question has apparently been answered.

Second, I’ve seen some Warren critics, including the president, suggest the “controversy,” such as it is, has less to do with racism and more to do with Warren exploiting her ethnicity to advance her career through affirmative action. This line of argument was already debunked; today’s revelations go further in slamming the door shut.

Third, Warren, who’s very likely to run for president, appears to see this as an early opportunity to set the record straight once and for all. Rather than having a racially-charged conspiracy theory hanging over her head, the Democratic senator is trying to turn the tables, capitalizing on the fact that she was telling the truth. Indeed, Warren has already challenged the president to send his $1 million check to the National Indigenous Women’s Resource Center.

But stepping back, it’s also worth pausing to appreciate the larger context. Donald Trump championed the racist “birther” conspiracy theory, and Barack Obama released his birth certificate. Trump championed the equally ugly “Pocahontas” conspiracy theory, and Elizabeth Warren released the results of a DNA test.

With these Democrats choosing full disclosure over secrecy, maybe Trump could … I don’t know … maybe release a tax return or two?