Donald Trump celebrates his first Independence Day in office with the country more polarized than ever.

In the United States in 2017, in-laws are more than just the cause of family squabbles about how to barbecue − the activity that unites the country on its national holiday, the Fourth of July. In-laws are part of the battle of ideas.

Here are the numbers to prove it: 30 percent of conservatives say they would be “unhappy” if a close relative married a Democrat, and 23 percent of liberals say they would feel the same if a loved one went with a Republican. Such rejection is not based on ideology; it’s aimed at people who are merely affiliated with a different party. That is, it’s not enough to be a “centrist” Democrat or Republican. You have to be a “real” one. Now that that’s cleared up, we can proceed to argue about how to cook the hamburgers.

It’s possible that the level of rejection toward members of the other party is even higher, because those numbers are from a Pew Research Center study conducted in 2014. Now political disagreements are sometimes violent. Three weeks ago, the second-highest ranking Republican in the House of Representatives, Steve Scalise, miraculously survived attempted murder by Democratic extremist James Hodgkinson. Twenty days earlier, Ben Jacobs, a reporter from the British newspaper, The Guardian, asked Greg Gianforte, a Republican candidate for the House, a question about the health care reform bill being debated in Congress, and Gianforte responded by wrestling Jacobs into a chokehold. Gianforte didn’t just win the election the next day. Within 24 hours of having literally broken Jacobs’ glasses, his supporters had donated $117,000 to his campaign.

Beating up the press is viewed favorably by a part of the American public. Donald Trump has called the media “the enemy of the American people,” and 51 percent of his voters agree with him, according to a poll from research firm, YouGov. So it should come as no surprise when the commander in chief of the United States posts videos on Twitter in which he beats up TV stations.

The president’s strategy is a very effective one. With his agenda at a standstill, the International Monetary Fund has lowered its growth forecast for the United States, since the world’s largest economy is basically running on autopilot. So Trump focuses on keeping the flame of his fans’ support alive. The things he says may not follow any clear logic, but they are extremely effective. With his tweets about MSNBC journalist Mika Brzezinski (who’s also the daughter of former President Jimmy Carter’s late national security advisor) and the video of him punching CNN, Trump has completely buried the stories published in The Wall Street Journal about how two of his closest aides − his chief political strategist, Steve Bannon, and his spokeswoman, Kellyanne Conway − allegedly worked with the Russian government and several hackers to steal emails from the Hillary Clinton campaign and the Democratic Party during the 2016 presidential campaign.

He’s also succeeded in making sure no one notices a law that will allow places of worship to campaign for political candidates. On May 18, in a meeting that wasn’t at all publicized, the president met in the White House with the highest-ranking Republicans from seven states that will be key in 2020: New Hampshire, Ohio, Pennsylvania, North Carolina, Colorado, Iowa and Michigan. Trump may not know how to govern, but he does know how to campaign. As one of his supporters says: “The only thing we’re worried about is him getting tired and leaving.”*

The problem is that Trump isn’t a candidate; he’s the president. And constantly fanning the flames of division can be dangerous. Just ask Thomas E. Ricks, who writes about defense issues for Foreign Policy magazine. In March, he conducted a survey on the magazine’s website in which he asked his readers − most of them experts in international relations, defense issues, and political science − if they thought that the United States was at risk of falling into a civil war or a period of “widespread political violence.” The readers felt there was an 18 percent chance of this happening. But when Ricks asked company executives, people who work in think tanks and universities, and senior administration officials, they raised that number to 30 percent. And on June 28, before going on vacation, Ricks wrote on his blog: “I have received several notes saying that number may be too low.”

This is more serious than a fight among in-laws.

*Editor’s note: The original quotation, accurately translated, could not be verified.