Typical exceptionalist bullshit.
America waited two years to join the war, in which time the UK pulled off a number of exceptional manoeuvres to keep the Germans at bay, the Russians lost more people fighting the Germans than all other countries combined and so on. Had they not, America's late entry into WWII would have been too late.
There's nothing exceptional about swooping in at the end and claiming all of the credit. Oh, wait, no... it's exceptionally rude, stupid and ahistorical.