As Finland and Sweden move to apply to join NATO, the organization should prepare to grant the requests in an expedited process.

The sooner those two nations are in NATO, the safer everybody will be.

The decisions by those Scandinavian nations to leave “non-aligned” status is a big deal, as Sweden has maintained neutrality for two centuries and Finland fought only defensively during World War II and has retained what amounts to a separate peace with Moscow ever since.

Just in the past six months, though, public opinion in both countries has shifted dramatically, from its long-standing, overwhelming support for neutrality to strong support for joining NATO, such that even Sweden’s Green Party isn't against NATO membership. Russia’s invasion of Ukraine and saber-rattling against Moldova and the Baltic states apparently made both Finns and Swedes distrust the Kremlin entirely. The Finns, with the experiences of first subjugation and then from 1939-40 invasion by the Russians, have historical reasons to be wary of Russian aims.

Why, though, should NATO want to add two more nations to its mutual-defense commitments? Despite what the emotionally twisted Russian dictator Vladimir Putin says, the two Nordic nations pose no offensive threat against Russia. But through control of Baltic Sea lanes, they are well positioned to help stop Russia from using its northern ports to project sea power if Russia attempts to conquer more territory or sovereign nations. NATO could be particularly reliant on Nordic assistance if Russia tries to annex NATO nations Lithuania, Latvia, and Estonia.

NATO is a purely defensive alliance, a fact President Joe Biden should stress in public more than he does, and Finland especially, with its well trained armed forces, can mightily help with the common defense.

Worrywarts who listen to Putin’s threats to attack if NATO membership expands don’t understand the balance of forces. First, Putin knows Finland on its own is no easy target, with a reserve military force of 900,000 and its historically proved record of using tough terrain to its advantage successfully to repel the Soviet invasion of 1939. Second, Putin knows NATO’s combined force of 3.5 million readily available military personnel dwarfs Russia’s active-duty 900,000, and he now knows that his forces are too weak even to overwhelm Ukraine’s 200,000.

And as former national security adviser John Bolton told me in a May 13 interview, “Neither the Soviets nor the Russians have ever crossed a NATO border, and I don’t think [Putin] is going to do it this time. … It’s not going very well right now [for Russia] in Ukraine, before he [even] gets into attacking a NATO country.”

And by rallying formerly neutral nations such as Sweden and Finland to NATO’s side, the invasion of Ukraine creates a great opportunity to add to collective NATO defense while public opinion in those nations is so strongly in favor of joining. Indeed, with Russia bogged down in Ukraine, the chances of it opening another front in response to NATO expansion are slim and none.

That’s why it behooves NATO to move rapidly to process and accept the Scandinavian applications for membership: Russia is too weak now to open a second front, and once those nations are full NATO members, Russia is too weak to take on NATO as a whole. The only time Russia reasonably might attack is if it finally achieves success in Ukraine and the Nordic applications are still pending rather than formalized into an automatic collective-defense commitment.

The shorter NATO makes that putative window of semi-opportunity for Putin, the better.