When asked why Ukraine mattered, a White House national security adviser answered that Vladimir Putin’s threat to invade that country was deeply destabilizing to the transatlantic community—and that borders and national sovereignty mattered.

That response triggered howls of outrage from those distressed by President Joe Biden’s de facto open-borders policy. Biden’s policies have created a massive flow of illegal immigration that has destroyed security along our southern border and imperils our own national sovereignty.

Critics asked how Biden could justify rushing thousands of troops to assist Ukraine and defend the borders of NATO, yet stubbornly neglect the chaos at our border. It’s a fair question. But it’s a question that misses the linkage between the border crisis here and the border crisis in Ukraine.

By relaxing U.S. border security, Biden sent a strong message to Putin that the new man in the Oval Office was not a serious president. And that is a big part of why there is a crisis now on NATO’s frontier.

>>> How the Ukraine Crisis Could Become a Disaster for Russia

Biden’s refusal to assure border security or enforce laws against illegal migration literally advertised for illegal human traffickers and cartels to “bring it.” The result: the least American secure border since the days of Pancho Villa.

In addition to refusing to defend U.S. borders, Biden also a proposed a defense budget that didn’t even cover the cost of inflation. That was followed by a cowardly and disastrous withdrawal from Afghanistan.

Putin could not help but interpret all of this as weakness. This impression was only reinforced when Biden officials signaled that America planned to do nothing to support Ukraine in the event of crisis. Indeed, their plan was to outsource the security of Europe to the Europeans, even though the transatlantic community is the joint responsibility of all the members of the Atlantic alliance.

Presented with these displays of unprecedented weakness, how could Putin not test the West?

The testing isn’t limited to Ukraine. Russia has already engineered a broader border crisis in Europe, trying to flood Middle Eastern refugees through the border with Belarus. Odds are this won’t be the last engineered border crisis. What will prevent the Russians or the Chinese from paying countries to flood the U.S. with millions more “refugees”? Exactly nothing.

The crisis in Ukraine is just part of a growing global attempt to exploit Biden’s inept leadership. We have reached a point where the U.S. military should be involved in responding to many aspects of the crisis.

Experts like former U.S. Customs and Border Protection Commissioner Mark Morgan and former Immigration and Customs Enforcement Director Tom Homan will tell you the military has a role to play in jump-starting an effort to reclaim our border and finish the wall. Do this, and America’s enemies will take notice.

>>> Change the European Chessboard on Russia

Further, regardless of how the Ukraine crisis plays out, the presence of a strong conventional and strategic deterrence will be key to forestalling Russian efforts to destabilize the transatlantic community. That means resuming the previous administration’s campaign to pressure our NATO allies to contribute their fair share to the common defense. It also means continuing to rebuild—not reduce—America’s military might.

Our allies also have work to do. Europe isn’t acting with confidence against Putin because it frets over the possibility of Russia cutting off gas supplies in the middle of winter. A victim of its own overly ambitious green agenda, Europe needs to dump Nordstream II, increase LNG imports from reliable partners, develop their own natural gas assets and get serious about nuclear energy (and perhaps even clean coal). A number of European nations would be excited to jump on this agenda with U.S. support, even as a responsible private sector continues to develop the capabilities of an efficient and effective green economy.

The common factor in both our border crisis and the Ukraine crisis is the feckless leadership of Joe Biden. The last president showed that there are policy solutions to both porous borders and Putin’s saber-rattling. President Biden needs to change course and resume those effective policies, starting now.