STANFORD – Strange as it may sound, vaccines are now the key to reviving the transatlantic relationship. Former President Donald Trump’s “America First” administration had left ties between the United States and its European allies badly frayed. So, in his address to the Munich Secutiry Conference in February, President Joe Biden thought it best to reaffirm America’s support for Article 5 of the North Atlantic Treaty: an attack on one NATO member would be considered an attack on all