President Trump tweeted a fictional claim about WWI-era General John Pershing Thursday afternoon, telling his followers to "study it." This is one of several times Trump has cited the debunked claim about Pershing.

The fictional story he's referring to: Pershing, around the time of the Philippine-American War, killed 49 Muslims with bullets dipped in pigs' blood, and spared the 50th person so that he would take the last bullet to his people and tell them what happened.

Why? Trump has referenced this story repeatedly at rallies both during his campaign and his presidency as a way to give credence to his claim that the U.S. should "go much further" than waterboarding suspected terrorists.

Timing: The tweet came hours after a terrorist attack in Barcelona left at least 13 people dead and more than 50 injured.

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Post-debate poll finds Biden strong on every major issue

Joe Biden speaks Friday about "The Biden Plan to Beat COVID-19," at The Queen theater in Wilmington, Del. Photo: Drew Angerer/Getty Images

This is one of the bigger signs of trouble for President Trump that we've seen in a poll: Of the final debate's seven topics, Joe Biden won or tied on all seven when viewers in a massive Axios-SurveyMonkey sample were asked who they trusted more to handle the issue.

Why it matters: In a time of unprecedented colliding crises for the nation, the polling considered Biden to be vastly more competent.

Bryan Walsh, author of Future
4 hours ago - Science

The murder hornets are here

A braver man than me holds a speciment of the Asian giant hornet. Photo: Karen Ducey/Getty Images

Entomologists in Washington state on Thursday discovered the first Asian giant hornet nest in the U.S.

Why it matters: You may know this insect species by its nom de guerre: "the murder hornet." While the threat they pose to humans has been overstated, the invading hornets could decimate local honeybee populations if they establish themselves.