Very true, Bob, I apologize.
Two ships come to mind that no one has put on the table. One American and One English (Yeah I know but this one is important, 'cuz we copied it her idea, TAKE THAT! 
The S.S. Savannah, First atomic/nuclear drive freighter. We never went anywhere it the idea because bad people could get their hands on the stockpile?
The Cutty Sark because she was the first composits ship and gave the correct idea that metal could be covered by wood without fouling cargo?
Jake
I see the Tregurtha where I work once a week locking in to go up the upper St. Mary’s river to get her cargo. I work at the Soo Locks and I get to see her up close.
Let’s face it, guys. American naval history is replete with historically significant ships. That is part of the joy of having been professionally associated with the U.S.N. for such a large part of my life (33 years). It also accounts for the joy of studying its history and modelling its ships!
Bill Morrison
True enough…but what are some of your favorites???
Suh, as much as it pains my Southern heart to say it. I would have to admit the "infernal Yankee machine known as the Monitor would have to be one of the most historically important vessels at least in modern industrial history. It laid the foundation for the design of all modern steel warships as far as innovation much as the Renault FT-17 tank did for modern tank design. All modern warships (and armored main battle tanks) can trace their roots back to these two designs. Rick Martin
I think if we are going to look at American vessels, certainly BOTH ‘Monitor’ and ‘Merrimac/Virginia’ must rate near the top of the list, as marking the end of the significance of the wooden warship as a major component of any fleet in the world. As far as favorites are concerned, certainly the USS Essex frigate during the 1812 war, for leading the British such a merry chase around half the world, and the same can be said for the CSS Alabama in the Civil War. Of more modern ships, I think the fleet carriers ‘Lexington’ and ‘Saratoga’ top my list for showing very early on just what a full-sized fleet carrier should be like (not just some experimental rubbish like HMS Furious or IJN Akagi), and of course, the battleship USS Missouri, for her role in WW2 and even more, for her role in the First Gulf War, as I could see the effect of thos big guns (we had to get them to stop firing, as their rounds were literally changing the geography so much, our maps would have been useless!)…
I’m just kinda spit-ballin’ here, but what about PT-109? Granted, her service may not have been exemplary (though she and her crew did their part when called upon), but, obviously, she played a big part in defining the ‘heroic’ career of a future president (let’s not get into a tangential political argument about JFK here, OK, fellas…? [}:)])
Not sure how much the boat was significant, as were the actions of its commander after it was sunk (you might say the same thing about the ‘Hanoi Hilton’ being significant because of its relationship to one of its survivors)…
…good points…
Okay brace yourselves its the love boat!.. HAH" got ya.
You might also say the birchbark canoe, as it certainly was distinctively American, and was used for everything from exploration to transportation to warfare… How would the West have been won without the canoe??
taking in your thoughts, and looking back. I’d like to add the Viking “long boat” as one (but not the first) of the first boats to hit the shores of the North American Continent. Actually the Chinese were here before the Native Americans even thought about crossing the land bridge in the Artic. But wait a minute I can now see my first wife at the helm of the Viking Cruiser with her metal helmet (with the horns sticking out the sides of course). Always had an idea she was lieing about her age!
gary
Well, the Viking longship was not an American boat, but a European one, so should not count. Also, I think you will find the Native Americans here in America by at least 14,000 years ago (some say 20,000), and that significantly predates any Chinese arrivals (I have heard some claims of stray Chinese ships on the West coast perhaps as early as 500 AD, but nothing before that, and of course, the really significant Chinese explorers weren’t until the 15th century AD, and I haven’t heard any actual evidence of them coming East, only to India, Africa, etc…
searat, the birch bark canoe is north american indian design not american as they are used here in canada too.
True, but only the very southernmost Canada, as big birch trees don’t grow that far North, and other barks were used up that way… In any case, a bit more ‘American’ than a Viking longship, wouldn’t you say? They were used by everybody, from Indians, to Voyageurs (both Canadian and American) all the way to the Rockies, and South to New Orleans, as well by various military expeditions and patrols everywhere West of the Allegheny mountains, and each group altered the design to fit their needs (as did the Indians as well)…
And completely non-naval. I’m not saying insiginificant, just not within the bounds of this topic.
‘not Naval?’ Well, maybe not in the conventional sense, but certainly canoes were used a lot for reconaissance and river work by Naval and other military forces (like in the St Lawrence, the Great Lakes, etc.)… Also, there was a large sea-going canoe that was used a lot down in the Caribbean in the 16th and 17th centuries. In effect these ‘Canoas’ were more like galleys, and could be both sailed and rowed, and were used by the Spanish and pirates as well… My understanding is that they were developed from the native war canoes used by the Caribs and other island natives…
I would think a vessel like the Hunley would be significant. From that day forward, seaman had to look below the water, as well as above.
Grymm
National Geographic has said many times that the first (and oldest) setlements in North America are Chinese, and predate the American Indian by hundreds of years. There were Chinese settelments all over the west coast. I know that in these days it’s not politically correct, but this has been proven out many times over.
In the part of the country I live in there are some of the oldest settlements (Native American) anywhere, and rarely does one go back 5K years. But there are a small handfull that are about 10k years old.
gary