After Ukraine became independent and forfeited the world’s third-largest nuclear arsenal, the West could have loosened the purse strings to guarantee the country’s economic independence. After the 2004 Orange Revolution, the West could have embraced Ukraine’s Western aspirations, accelerated an EU Association Agreement and a NATO Membership Action Plan, and driven domestic transformation to shield Europe’s largest country from nascent Russian revanchism. After the 2014 Revolution of Dignity, the West could have invested in a strategic security partnership with Ukraine that would have made the costs of a Russian offensive prohibitively high. Yet none of this came to pass.

Instead, for two decades, the U.S. entertained illusions about what might be accomplished with Russia, a reluctant partner, while remaining oblivious to opportunities in Ukraine, a far more willing one. In its relationship with Russia, the U.S. had limited prospects of achieving any objectives outside of arms control, whereas with Ukraine it might have successfully influenced regional development…

Nevertheless, U.S. leaders cannot absolve themselves of guilt by claiming they did all they could to prevent another invasion; they offered a necessary response, not a sufficient one. Like every administration since the end of the Cold War, Joe Biden’s fell victim to wishful thinking about the Kremlin’s ambitions in Ukraine and Russian President Vladimir Putin’s basic commitment to international norms. In doing so, the Biden administration continued the decades-long practice of allowing deterrence to erode. The paths to prevention were not taken.