Define "Drink of Choice" because that sounds pretty broad and very easy to generalize to be honest
You might as well make the argument that Coca-Cola was America's "Drink of Choice" as it's a prime symbol of Americanism and was and still is a popular drink in the US and around the world, and Coca-Cola is actually about as old as Milkshakes are (both were invented in the mid-1880s) so I honeslty believe Coke has more legitimacy to this title than anything else