It's worth remembering that the distance from Dublin to Belfast is a scant hundred miles, less than the drive from New Albany to Indianapolis.
Note also: The Brexit article (below) refers to cans and bottles, not kegs. Clarification is necessary, as I hope to return to the business of selling Guinness, sooner rather than later.
First, from January, 2017:
After a 63-year absence, Guinness Brewery will once again have a working brewery in the United States.
The Diageo-owned brand will be creating a version of its Dublin-based Guinness Open Gate Brewery in Relay, Maryland.
While the iconic Guinness Draught, Guinness Foreign Extra and Guinness Extra stouts will still be brewed in Dublin and exported to the U.S., the new brewery will focus on new Guinness beers created for the U.S. market.
About that Brexit thingy ...
Why Brexit could mean a pricier pint of Guinness at The Economist
IT MIGHT just be Ireland’s most famous product. And indeed, all of the Guinness that is drunk in the world is brewed at the St James’s Gate brewery in east Dublin. But the dark beer is then transported north, in tankers that have become known as “silver bullets”, to be canned and bottled in east Belfast before returning to Dublin for export. Diageo, the multinational company that owns Guinness, says that its silver bullets make some 13,000 border crossings a year. It estimates that even a short delay of 30 minutes to an hour for customs checks would add about €100 ($115) to the expense of each trip, costing the firm some €1.3m a year. If that happened, the price of Guinness might have to rise.