The arrival of the USS Barry in Cobh next month is eager ly awaited by the townspeople and local business concerns for whom such visits are a huge part of the town's economy.
The US navy, according to the US Ambassador, Michael Sullivan, regards Cobh as a "special stop". Cobh welcomes the visitors.
When The Holy Ground, one of the great seafaring songs, was composed, it was sung about Cobh seafarers. The British naval presence, the handover of the ports, the luxury liners which came to and went from Cobh were all part of its history as it waxed and waned.
Now, the Naval Service is based at Haulbowline, just across from Cobh, its personnel also contributing hugely to the economy of the town. In good times and bad, Cobh was always about the sea.
Speaking to The Irish Times from Washington during the St Patrick's Day celebrations last weekend, the ambassador said he had become aware that Cobh was one of the more preferred calls by US naval vessels when the sailors were due for rest and recreation after a tour of duty.
"They get a great welcome and they get on very well with the people of Cobh." It might be said that the people of Cobh get on very well with them too. In the town there are stories of shore leave friendships that develop into lasting contacts over the years.
When a destroyer such as the USS Barry comes to Cobh it has on board at least 300 people. The vessel is of the Arleigh Burke class - a fleet escort - and would be one of the smaller US fighting ships afloat.
"We appreciate the hospitality shown to our people and I think it works both ways," Mr Sullivan said. He was speaking in Cobh when he came to address a Chamber of Commerce meeting last week, but he forgot to mention that he was dashing off to Washington for the shamrock bash.
In any event, his visit started a discussion among other people in Cobh about what the US military presence meant now that the nature of the port's role has changed.
Cobh was the embarkation point during the Great Famine when wakes were held by families in the town who never expected to see a son or daughter again. Later it became the port of call for the great liners bearing the rich and famous.
The US navy is now an important part of the Cobh economy. When everything is taken into account, the visit of a US naval vessel might bring £500,000 to Cobh in a short time - the visit might last only three days. You can see why the USS Barry will be welcomed.
One ship, one crew. So where is all the money generated? For a start, thousands of people will avail of the opportunity to visit one of these awesome fighting machines during the open days which form part of every visit. There have been protests over the visits in the past but nowadays the city quays in Cork play host regularly to NATO ships which come calling as a matter of "courtesy".
Naturally, no one takes this at face value and it is well understood that while this State does not participate formally in NATO, we are behind-the-scenes members or at least facilitators.
So if that's the bottom line, towns like Cobh should benefit as best they can, and they do. When the USS Barry ties up in Cobh on April 14th there will be considerations other than the tourism attraction. People will come from all over Munster as they normally do to see the vessel.
As of now, the visit has not been announced formally but it is going to happen and when all the visitors have come and gone, some cheques will have to be written by the Americans.
The rope boats will have to be paid - these are the ones that help to tie up such vessels - there will be pilotage fees; bunkers - namely fuel - will have to be taken on board locally and as many as 30 tankers could be required to bring it to the ship.
Lorry-loads of bread, butter and fresh vegetables will also come alongside to provision the Barry.
Then there's the side of things ashore. As I understand it, there is some sensitivity about how this works but I can say that be fore a US destroyer arrives in a port, some groundwork is done. The naval authorities need to know if there are places - usually bars - which would be better avoided by their people.
Local contacts are made and an advance man comes to see those who are in the know.
If a sailor steps out of line, there will be no more shore leave until the vessel reaches its home port and then the music will have to be faced. For someone who breaks the code of conduct, it does not sound like a nice passage home.
Michael Sullivan has a gra for this place and wants to know more about the genesis of his roots. It would not be the first time that a US president or diplomat wanted to find out more about the ancestral home.
He thinks his people came from the Castletownbere area and that his great-grandfather, James Sullivan, originated there. He believes that on the maternal side there is a Longford connection.
Mr Sullivan is determined to find out about these things, and a local historian in west Cork is helping with the quest. By the way, this ambassador's hallmark is his stetson hat - he rarely goes anywhere without it - not even to events run by a chamber of commerce. That makes him all the more refreshing. Let's hope he finds his roots.