When President Donald Trump announced tariffs against America's closest European allies over the weekend, he probably didn't expect the sharpest pushback to come from his own party. But that's exactly what happened, with Republican senators warning that threatening NATO partners over Greenland is the kind of strategic own goal that makes adversaries very happy.

GOP Senator: This Is Putin's Dream Scenario

Senator Thom Tillis (R-N.C.) didn't mince words on Saturday, calling out the administration's response to Denmark sending a handful of troops to Greenland for training exercises. The tariffs, he argued, are solving a problem that doesn't exist while creating real ones.

"This response to our own allies … is bad for America, bad for American businesses, and bad for America's allies," Tillis wrote on X.

Then came the kicker: "It's great for Putin, Xi and other adversaries who want to see NATO divided."

Tillis also took aim at whoever is whispering aggressive Greenland strategies into Trump's ear, calling the notion of seizing territory from an ally "beyond stupid." He warned the approach would damage Trump's legacy and undo years of effort to strengthen NATO.

Alaska Senator Calls Tariffs a 'Profound Mistake'

Senator Lisa Murkowski (R-Alaska) piled on, describing the tariffs as "unnecessary, punitive, and a profound mistake." As someone representing a state with serious Arctic interests, Murkowski knows the region matters. But she warned that forcing NATO partners to scramble over Greenland is exactly what Putin wants.

"That plays directly into Putin's hands by threatening the stability of the strongest coalition of democracies the world has ever seen," Murkowski wrote.

She also made a broader constitutional argument, urging Congress to reclaim its authority over tariffs so they can't be "weaponized" as political leverage.

The Deal: Buy Greenland or Face Tariffs

So what sparked this Republican revolt? On Saturday, Trump announced that the U.S. will slap 10% tariffs on Denmark, the United Kingdom, France, Germany, and other European nations starting February 1. Those tariffs jump to 25% on June 1.

The tariffs stay in place, Trump said, "until such time as a Deal is reached for the Complete and Total purchase of Greenland." The president argues the Arctic island is essential to U.S. national security, which isn't entirely wrong. But threatening allies with economic punishment to force a real estate transaction is, let's say, unorthodox.

Bipartisan Chorus of Criticism

The backlash extended well beyond the GOP. Senator Bernie Sanders (I-Vt.) called the tariff threat "insane" on Saturday and urged Congress to block it, warning that undermining key alliances has consequences.

Even John Bolton, Trump's former national security adviser and hardly a dove, acknowledged Greenland's strategic importance but warned that threatening tariffs would make Arctic security harder to maintain, not easier.

Senator Chris Coons (D-Del.) announced he's leading a bipartisan congressional delegation to Denmark to meet with Danish and Greenlandic leaders. His message: Congress stands united in supporting NATO allies and opposing unnecessary threats against trusted partners.

Representative Don Beyer (D-Va.) went further, calling the plan illegal and catastrophic, and urging both Congress and the Supreme Court to step in.

The whole episode highlights a rare moment of bipartisan agreement, even if it's agreement that the administration's Greenland gambit might be creating more problems than it solves.