As the House’s impeachment inquiry kicks off, stoking partisan tempers online, Facebook and Twitter are scrambling to deal with the fallout.

Why it matters: Social media platforms that set out to “bring the world closer together” and help people “share ideas and information” are finding that there is no bottom to the hole they’re in now that their services have become political battlegrounds.

Driving the news: President Trump’s tweets have often been intemperate, but since the announcement of the impeachment inquiry they have grown even more combative and menacing.

Trump quoted a conservative minister’s argument that removing him from office would set off a new American civil war. He also twice suggested that Rep. Adam Schiff, the Democratic congressman who chairs the House Intelligence Committee, might be tried for treason.

A Harvard law professor told Newsweek the “civil war” tweet was grounds for impeachment, and Republican Rep. Adam Kinzinger called it “repugnant” (on Twitter).

In September, Democratic Rep. Ilhan Omar said Trump’s retweet of a false video claiming to show her celebrating the anniversary of the 9/11 attack had put her life at risk.

In all these cases, the president used his position and his Twitter soapbox to threaten political opponents, his critics argued. They cranked up their longstanding call for Twitter to suspend his @realDonaldTrump account.

Twitter’s rules bar targeted harassment and threats of violence against individuals or groups.

But Twitter has long held that it will move with extra caution when it comes to public figures — people who “may be considered a topic of legitimate public interest by virtue of their being in the public consciousness.”

In June, Twitter announced that, in cases where its moderators had determined that a particular tweet violated its rules but was being allowed to remain online anyway for this reason, it would notify the public with a “gray box” notice on the message.

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