As Vladimir Putin continues to amass troops on the border of Ukraine, there is a growing sense that the die has been cast, and that invasion is unavoidable. President Joe Biden, in a news conference last week, said, "My guess is he will move in. He has to do something."
That may be true, but it does not mean we cannot further complicate Putin's calculus while we still have a chance. At minimum, doing so could delay an invasion, giving Ukraine more time to prepare.
At the same time, there is still hope, however slim, that we can deter Putin. We owe it to ourselves and our allies to exhaust every option to deter him before an invasion begins.
As a start, Congress must immediately pass the Defending Ukraine Sovereignty Act. The legislation has the backing of the Biden administration, but time is running out to pass it for maximum effect.
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The bill includes crippling sanctions against Russia that will trigger upon further military aggression in Ukraine as well as measures to combat Russia's destabilizing disinformation campaigns. Perhaps most important, the bill mandates a massive and immediate increase in defensive aid to Ukraine.
Specifically, the legislation would expedite procurement and delivery of defensive weaponry to Ukraine by using the Special Defense Acquisition Fund and lease programs. On top of the $650 million in defensive weaponry and support that the Biden administration has already committed, the armaments that would swiftly arrive in Ukraine under this legislation would make the prospect of invasion more complicated for Putin.
Congress is moving too slowly
Inexplicably, Congress is taking its time on this critical legislation. Passage of this bill before any invasion will be key to its success. Triggered measures must be put in place now to signal the concrete costs of Russian military aggression in Ukraine.
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We need to ensure that threats of unprecedented sanctions and severe consequences for Russia will prove credible.
And yet, following the Senate's marathon session on voting rights, Congress is in recess. When it returns, Congress may find that passage of this bill will come too late. Recognizing time is not on our side, Congress must move this bill immediately, and get it to President Biden for his signature.
Alongside the provision of weaponry, we should also show greater commitment to holding Putin in check, should he choose to invade. We must deploy more forces now to Eastern Europe to deter Russian aggression beyond Ukraine and contain the fallout of a major war.
Invasion must have high cost for Putin
Putin must be made to understand that his aggression will be limited, contained and costly. Deterrence against further aggression and coordinating with our allies will also help prevent a bilateral confrontation involving U.S. troops.
Vladimir Putin is an aggressive thinker, but he is not irrational. He will take all that he can as long as the cost is bearable. While diplomatic efforts to dissuade him were necessary and important, they came without the movement of troops and equipment that would have significantly raised the costs of invasion.
Thus, he has continued the buildup - possibly to the point of no return. But while there are still seconds on the clock, we can and must act to avert an invasion and the spillover that would suck America into another European war.
There is no more time left to waste.
Alexander Vindman is the former director of European Affairs for the U.S. National Security Council, a senior adviser to VoteVets, and author of "Here, Right Matters."
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This article originally appeared on USA TODAY: Russia invasion of Ukraine can be stopped. But U.S. must act now.