Within days of taking office, President Joe Biden’s campaign-trail veneer of tough-talking Russia hawk melted away to reveal a weak-kneed appeaser unwilling to constrain the Russian bear. Today, Russia may be on the brink of invading Ukraine because President Biden’s weakness has emboldened Vladimir Putin. In his first week in office, Biden agreed to extend the one-sided New START nuclear-arms treaty. He ignored nearly two thousand Russian tactical nuclear weapons outside the scope of the treaty and took no actions to constrain China’s massive nuclear buildup—both critical U.S. priorities related to New START. A no-strings-attached U.S. extension of New START...