In a blatant attempt to test NATO unity and President Donald Trump‘s resolve as leader of the free world, Russia launched an unprovoked aerial drone incursion into Poland overnight Tuesday into Wednesday. At least 19 Russian attack drones broke into Polish airspace from Ukraine and Belarus, some ranging many miles into Polish territory. NATO forces shot down four of them.

This is a serious test of the West by the Kremlin. It requires a prudent but firm response.

Recommended Stories

• A sadly necessary Senate rule change on nominations
• What the murder of Charlie Kirk means
• Supreme Court rightly rules for immigration enforcement in Los Angeles

Trump should reaffirm his commitment to NATO, an alliance that continues to serve Americans well. NATO should warn Russia and Belarus that any unmanned drones in Ukrainian or Belarusian airspace within 10 miles of the Polish border may be shot down.

NATO’s deterrent purpose is designed for moments such as this. Poland is one of the most reliable American-NATO allies. At 4.7% of GDP, it spends the highest percentage of its GDP of any NATO member on defense. Recognizing this commitment and the heavy pro-American sentiments across the Polish political spectrum, the U.S. should be resolute in defending its eastern flank ally. With Belgium, the host of NATO headquarters, barely reaching NATO’s 2% of GDP minimum defense spending target, Trump should push for NATO headquarters to relocate to Warsaw.

Coming on the heels of a visit by the Polish president to the White House last week, it is clear that Russian President Vladimir Putin is prodding NATO to test its weaknesses. This fits a recent trend of gambits by Putin to see how Trump responds to his intimidatory antics. To his credit, Trump confirmed in last week’s meeting that he had no plans to remove U.S. Army forces from Poland. The president has recently bolstered his previously cautious statements of support for NATO amid his unparalleled success in persuading alliance members to spend more on defense.

In its typically self-righteous and disingenuous fashion, the Kremlin denies that it intended to fly drones into Polish airspace. Some Russian military commentators have more credibly suggested that this was a “stress test” of Polish and NATO air defenses to see how they would fare in a surprise attack. Poland and NATO passed that test, but only barely. While a number of fighter, refueling, radar, and intelligence aircraft from different NATO member states were launched during the incursions, too many Russian drones got too far into Poland before being shot down. NATO is discussing steps to bolster air defenses in Poland, but this incident reinforces the urgent need for NATO’s European member states to get serious about building their air forces.

But Putin isn’t simply testing NATO, he’s also testing Trump. Putin has noted Trump’s oft-stated concern that the Ukraine war might lead to “World War Three.” By dangling his drones over NATO’s Article Five mutual defense security guarantee, Putin wants to see if Trump will put pressure on NATO and Ukraine to reduce tensions or, as he should, impose costs on Russia for its new aggression. Putin wants to see if Trump will stand up to him or crack.

Trump should teach Putin a lesson, confident in NATO’s present supremacy over Russia, and of U.S. military forces across the range of conflict, knowing the importance of the alliance for Western security, prosperity, and freedom. Putin, a former KGB officer, struck the first blow by invading the airspace of a close American ally. Since he has repeatedly made clear his willingness to threaten NATO territory (including U.S. territory and lives), Trump and NATO should respond in a way that demonstrates willingness to defend territory with military violence.

POLAND ACCUSES RUSSIA OF ‘PROVOCATION’ AFTER DRONE CRASH ON BORDER

The alliance should provide the forces necessary to destroy any Russian drones that approach within 10 miles of the Polish border. Force may then not be necessary. But if Polish leaders feel their country is threatened, they should have an alliance backing to defend it aggressively. Russia is weaker than Putin lets on. He can be put back in his box if NA shows it is prepared to shove him back in there.

Trump and NATO must be wary of the cost of inaction. Putin sees any sign of weakness or hesitation as blood in the water, and this leads him on to more attacks.