As a security vacuum in Europe grows, a wider, strategic question remains unanswered: Who is responsible for keeping Europe safe and free, and at what cost?

NATO’s 2 percent spending goal is a political basis for driving the debate on burden sharing. But that debate must lead to firmer action if NATO is to remain durable.

It is unrealistic to expect all NATO allies to spend 2 percent of GDP on defense. Yet the metric persists—and it has assumed a significance beyond its face value.

If NATO allies do not find their own strategic policy worth investing in, why should adversaries and rivals take the alliance seriously?

To solve their readiness and capability problems, NATO allies should shift their attention away from the meaningless 2 percent spending pledge.

NATO’s 2 percent target is practically useless and should be abandoned in favor of a more objective, more accurate measure of burden and risk sharing.

NATO, despite being the primary framework for transatlantic military cooperation, is still an alliance of independent states that have their own budgets and priorities.

NATO members have committed to boosting their defense capabilities. Beyond reversing downward trends in spending, what should allies do to meet that commitment?

Every week, a selection of leading experts answer a new question from Judy Dempsey on the foreign and security policy challenges shaping Europe’s role in the world.