In times of crisis, the need for strong international law and multilateral institutions is most urgent. This is the very time we turn to the rules, norms, and safeguards to prevent conflict and reduce the suffering of civilians in war. While it's hard right now to imagine Russia sitting down with the other nuclear-weapon States to agree new commitments to reduce and eliminate their nuclear weapons, that is precisely what is needed. As the world now works together to impose sanctions on Russia and to support Ukraine, we must be equally muscular and equally united in building out some multilateral institutions and strengthening international law. If we don't, how will we avoid a renewed arms race, more breaches of the UN Charter, more conflict, and a much more dangerous world? 