We just returned from a bipartisan visit to Denmark, and what we saw should concern every American.
As large public protests took place outside the U.S. Embassy in Copenhagen, our conversations with Danish and Greenlandic leaders made clear that President Trump’s threats to take Greenland have shaken public confidence in the United States and undermined the foundation of the trans-Atlantic alliance. Mr. Trump’s recent comments that downplayed NATO allies’ contributions in Afghanistan have deepened the crisis of confidence within the alliance and caused understandable public outrage across Europe.
This is now a moment of risk for our shared security, and it is entirely unnecessary. The United States has a standing defense agreement with Greenland dating back to 1951. Under that framework, the United States built and operated more than a dozen military installations on the island. It was Washington, not Copenhagen or Nuuk, that later concluded all but one of them were no longer needed.
For their part, Danish and Greenlandic leaders have repeatedly made clear they are willing to form a partnership with the United States on issues ranging from Arctic security to critical minerals. The people who actually live in Greenland, who are too often an afterthought in this conversation, would largely welcome a stronger U.S. military presence and renewed investment. There is no strategic objective here that cannot be achieved through cooperation.
Mr. Trump’s fixation on taking Greenland is unfolding at a time when the United States needs a strong, united front against adversaries that are working to expand their influence and undermine democratic alliances.
Russia is waging the largest land war in Europe since World War II, expanding its military presence in the Arctic, escalating cyber and hybrid attacks against NATO members and walking away from key nuclear arms control agreements. China has deepened its strategic alignment with Russia while escalating threats toward Taiwan, putting global supply chains and economic stability at risk.
In this environment, allied unity is not optional; it is a strategic necessity. Yet leaders of Arctic countries now speak openly of a “rupture” in our longstanding security and economic relationship.
Instead of strengthening our alliances, threats against Greenland and NATO are undermining America’s own interests.
Suggestions that the United States would seize or coerce allies to sell territory do not project strength. They signal unpredictability, weaken deterrence and hand our adversaries exactly what they want: proof that democratic alliances are fragile and unreliable.
Similarly, the on-again, off-again specter of tariffs and a trans-Atlantic trade war does not provide meaningful negotiating leverage. It spooks markets, wipes out wealth, distracts from higher priorities and erodes the trust we have built over decades.
In the midst of this, one crucial actor is hiding in plain sight. The U.S. Congress bears responsibility for reinforcing constitutional guardrails on the Trump administration’s policy toward NATO, with respect to both Greenland and to safeguarding our intertwined economic and security interests.
Congress cannot be a bystander when the stakes involve the sovereignty of an ally or the future of NATO. We have tools at our disposal to assert our authority and make clear to our allies that we will not tolerate further threats against them.
One immediate step is to legally block any potential attempt to seize or coerce control over allied territory.
That is exactly what our bipartisan NATO Unity Protection Act does. It prohibits taxpayer dollars from being used to blockade, occupy, annex or otherwise assert control over the sovereign territory of any NATO ally without that ally’s consent and approval by the North Atlantic Council. This is a necessary safeguard against an administration that has repeatedly shown it is willing to act first and explain later.
Pre-emptive legislation is unfortunately necessary. Our fellow lawmakers have a choice: assert their constitutional authority or wake up to decisions that have already been made without them.
During our recent visit, a Danish American approached one of us after a public event. She told us she worries that her son, who holds both Danish and American citizenship and is nearing Denmark’s conscription age, might one day be forced to choose between the two countries he loves. We heard from Greenlanders who can’t sleep, and who told us that their children are crying amid fear of invasion — not from China or Russia, but from the United States.
That fear would have been unthinkable just months ago. Today it is becoming part of how people in allied nations talk about the United States, and it is profoundly undermining America’s national interests.
This is not the future Americans want, and it is not the future we should accept. The United States has spent generations building alliances based on shared values, mutual respect and the rule of law. Those alliances remain our greatest strategic asset. The question now is whether Congress will defend them.
Jeanne Shaheen is the ranking minority member of the Senate Foreign Relations Committee. Lisa Murkowski is a member of the Senate Appropriations Committee.
The Times is committed to publishing a diversity of letters to the editor. We’d like to hear what you think about this or any of our articles. Here are some tips. And here’s our email: [email protected].
Follow the New York Times Opinion section on Facebook, Instagram, TikTok, Bluesky, WhatsApp and Threads.
The post Shaheen and Murkowski: Congress Must Defend NATO From Trump appeared first on New York Times.
