On Inauguration Day last year, many predicted that President Trump would abandon his bombastic campaign rhetoric and start behaving like a more conventional leader, especially as far as national security issues were concerned. Conventional wisdom assumed that all presidents make the transition from candidate to commander-in-chief. One year later, this week’s barrage of scandals have made it clear yet again that he is not going to change.

So now Trump supporters lean on a second claim. Ignore the tweets, they tell us; judge the president by his actions, not his words. It’s an argument worth closer inspection. When do words matter? When do Trump’s tweets or vulgar statements influence foreign-policy outcomes? It’s easy to get upset about the president’s statements we don’t like (and I confess I often do). But we should specify precisely how Trump’s rhetorical flares affect the United States’ national interests.

First, Trump’s words alienate other societies. Well before his latest insults hurled at Haiti and the entire continent of Africa, Trump’s language had diminished the United States’ standing among citizens in most countries in the world. A Pew poll conducted in 37 countries as early as spring 2017 revealed that a median of only 22 percent of those surveyed trusted Trump “to do the right thing when it comes to international affairs.” Shockingly, publics in at least a dozen countries friendly with the United States trusted Russian president Vladimir Putin more than Donald Trump. A more recent Gallup poll revealed similar results. Trump’s latest statements are likely to have pushed these numbers further downward.

To be sure, diplomacy is not a popularity contest. Most governments around the world will treat the United States based on their definition of their country’s national interests, not whether their citizens like Trump. But the president’s insulting and uninspiring words will make other countries less likely to work with the United States on such tough problems as North Korea, Iran and or Syria. Trump would never abandon his electoral base – a minority of Americans – to do a favor for French President Emmanuel Macron or German Chancellor Angela Merkel. Why should we expect these leaders to ditch their citizens to help Trump?

Second, Trump’s refusal to promote democratic or universal values undermines democracy and human rights activists fighting tyranny around the world. His embrace of strongmen undermines his credibility when he does speak out in support of anti-regime Iranian demonstrators. Trump’s indifference to democratic values also undercuts those in his government responsible for advancing human rights. American ambassadors making statements about human rights abuses in countries where they serve have little credibility today.

Some Trump supporters – both at home and abroad – celebrate this abdication of America’s moral role in the world. Earlier this week, Fox News television host Tucker Carlson tweeted, “America does not exist to protect and stand up for the citizens of other nations.” The history of the last century, however, suggests that the United States does benefit from advancing democracy abroad. Every enemy of the United States has been a dictatorship, including our enemies today. Our most enduring allies have been democracies. Rhetorical support for democracy and human rights is not just the right thing to do, but also an instrument for advancing U.S. security interests.

Third, Trump’s rhetoric of disruption often obscures instances of continuity with Obama administration policy and that of other previous U.S. presidents. To be sure, Trump has pulled the United States out of the Trans-Pacific Partnership, has pledged to move the U.S. Embassy in Israel to Jerusalem, and has threatened to withdraw both from the Paris climate agreement and the Iran nuclear deal.

Yet his administration’s actions don’t always coincide with the rhetoric. In Europe, Trump has not followed through on his earlier pledges to embrace Putin, look into recognizing Crimea as part of Russia or reduce U.S. commitments to NATO. Instead, his administration has remained committed to the Obama strategy of strengthening NATO, sanctioning Russian officials, and providing economic, political and military support for Ukraine. In the Middle East and South Asia, Trump’s policies of defeating the Islamic State in Syria, maintaining our military presence in Afghanistan, supporting our Arab allies and Israel while containing Iran, and deepening ties to India look very similar to those of previous administrations, including, for the most part, President Barack Obama’s. In Asia, Trump has not made good on his threats to start a trade war with China or renegotiate our alliances.

Few at home or abroad recognize these continuities, however, because of the president’s careless language. This gap between words and deeds may satisfy Trump’s domestic electoral base, but it does not serve U.S. interests. The distance between the president’s statements and his administration’s actions creates the impression that he is not involved in actual foreign policymaking or implementation. That image is not good for our diplomacy.

Finally, Trump’s words on North Korea create real risks and are a significant departure from both past U.S. policy and current diplomatic efforts by his own secretary of state. The dangerous situation on the Korean Peninsula does not allow us the luxury of disregarding his tweets. There is no greater sin in diplomacy than triggering military conflict based on misperception or misunderstanding, and Trump’s inflammatory rhetoric on North Korea risks precisely that.

In diplomacy, words are important. Loose talk threatens U.S. stature abroad, alienates allies, demoralizes democratic forces working against autocracies, confuses foreign and domestic observers about actual policies, and leads to potentially dangerous confusion on the issue of war and peace. As the Trump administration confronts thorny foreign-policy problems, his rhetoric limits rather than enhances the United States’ ability to achieve desired outcomes. As the president starts his second year in office, he should realize that talk is not cheap. Words do matter, and it is time for him to align his rhetoric more closely with U.S. foreign-policy objectives, policies and actions.