1) Four years ago, when Donald Trump was pulling further and further ahead in the Republican primaries — the inner-party contest for the presidential nomination — many people, both in the United States and abroad, believed that the office itself would restrain him if ever he were to win it. Even later on, as the election campaign entered its final months, many still forgave his offensive comments, the hate-filled tirades against his fellow candidate, his threatening of journalists, his mockery of people with disabilities. They thought it was just campaign bluster, that it would all right in the end. "The office shapes the man," as the saying goes. These past few years, the world has been forced to learn the bitter lesson that populists stay populists, regardless of the office they hold. Neither businesspeople nor politicians lose their contempt for others just because they've sworn an oath of office.

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2) How politicians speak about their political opponents and critics matters. Right now, we're seeing the long-term effects of the verbal poison Trump has been pouring over his country for the last four years. It's destroying society from within. The president's constant verbal attacks have caused the emotions of Americans to be dominated by hatred, anger, and contempt. Words aren't irrelevant — they're weapons. We must be rigorous in how we use them, even if it means running the risk of being seen as humorless or inflexible.

Murderous acts originate in the mind

3) Racism kills. But murderous acts have their origins in the mind. We cannot allow ourselves to be negligent in the fight against exclusion and everyday racism. In Germany, even today, there are still too many far-right elements in important institutions. Xenophobic jokes are still par for the course. Minorities are still singled out as scapegoats. Naturally, every country has its own specific history, with specific challenges resulting from that. But no society is free of racism, and we should all be continually questioning our thoughts and our actions.

4) I was there four years ago when Trump launched his campaign against the established institutions. I saw how he packaged his racism, his misogyny, his anger at the efforts of a functioning democracy to achieve the greatest possible equality of opportunity as a fight against the establishment — the elites. All politicians should heed the warning that this form of populism ultimately attacks the very foundations of democracy.

5) The US has also taken its self-destructive course because there are no longer any spaces where its citizens can speak with one another, no common ground between the barricaded worldviews of social media realities. Even for traditional media outlets, it's become nearly impossible to reach an audience that doesn't share their respective political views. This angry division has opened the door not only to homegrown conspiracy theories, but also to foreign powers with both concrete and murky political intentions.

I've become jaded

6) I don't know how you feel, but I sometimes catch myself and realize just how indifferent I've become when it comes to the actions of the current US president. Things that were simply unimaginable a few years ago are now the new reality: crass comments about other heads of state, threats, insults. Michelle Obama, the former first lady, once aimed to set a different standard with her now-famous words of advice: "When they go low, we go high."

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Here, too, the United States can serve as a warning. Respectful interaction is more than mere etiquette; it's also the basis for a truly democratic shaping of public opinion. I'm not saying that we shouldn't vigorously fight for what we think is right, both in the political sphere and in the media. But even a quick tweet should still be written with civility. In these days and weeks, we're seeing what can happen when a country loses respect for its institutions and, ultimately, for itself.