The leaders of the European Union are on the defensive. More than a year into the pandemic, only 3% of people living in the EU have received a dose of Covid-19 vaccine, compared to more than 15% in the UK and 10% in the US. And as pharmaceutical firms increasingly face production delays that are leading to shortages around the world, critics are blaming the 27-country bloc‘s experiment in collective bargaining for its slow and controversial vaccine rollout. Five weeks ago, when vaccinations began in the EU, European Commission president Ursula von der Leyen called this crisis “Europe’s moment.” This week, she had to defend the EU-wide effort to jointly negotiate and procure vaccines before an unhappy European Parliament. She’s not alone: French president Emmanuel Macron said his country’s rollout “is going at the pace that was planned,” even though it “may seem too slow,” and German chancellor Angela Merkel was asked to apologize to Germans who have been clamoring for more vaccines.