I guess this fits on a warbird board, some of it involves warbird history anyway-
I went to Hawaii for the first time a couple of weeks ago, and have added Pearl Harbor to the list of places that I've been that I think all Americans should visit at some point in their lives. Standing on the Arizona Memorial and looking up at the sky and trying to imagine the peace of that morning being broken by the sound of hundreds of attacking enemy aircraft, quite an amazing place. They've also added a couple of new museums in the last few years (and of course the Pacific Aviation Museum). As always, being on the site gives you a view of the distances and relationships of the various parts of the scene that you could never get from books and photos and etc. We did not get to the USS Missouri or the Bowfin as it was our first day there and still a little jet lagged, but were early going to the airport to go to Maui a few days later and I talked my girlfriend into going back to Pearl for a little while so I could walk around the Valor in the Pacific Memorial again and look out over the water at where Battleship Row was. Very moving place.
Hawaii was the 50th state I've visited, and I had flown small airplanes in 47 of them, so wanted to get in a flight there. I called the FBO listed on airnav.com at Dillingham Field on the North Shore and Scott told me that he was more of a fuel vendor, but had a Navion that I could fly as long as he went along also, so on our second day we did that.

I have to say that it was pretty cool flying around Oahu in a low wing retractable gear North American. Scott showed me where the remains of Haleiwa Fighter Strip are, where George Welch and Ken Taylor took off in their P-40s on that morning (and in "Tora, Tora, Tora!"), then we flew down the windward (East) side and back, and then up the central valley a bit so I could see Pearl Harbor from the air (from a distance, still pretty neat). The girlfriend got to ride in the back and saw whales, so she was happy, and I made a good landing.
Need to fly in Nevada and Utah now...
As for the other places, Ground Zero would be an obvious on the list, although it's such recent history that still directly affects all of us that it should be on a list of its own.
For historical sites of events that happened before I (most of us?) were born, that I think all Americans should visit, Gettysburg would be one, and Normandy the other, of the places I've been. You don't have to be a military person to stand on Omaha Beach and look up at those bluffs and marvel at what those guys did. I'd love to see Iwo Jima also, but it's a bit hard to get to.
For any nationality, if you want to see a pretty good scene of how war is hell (that's not what I typed, but OK), make a visit to the World War 1 battlefield at Verdun in France. It's impossible to imagine what it was like in hand to hand combat inside the giant stone forts there, and the ground for miles around is still churned up with shell holes from the fighting in 1916. And to look through the windows beneath the Ossuary and see the bones of 130,000 unknown soldiers is very sobering.
The American forces also saw lots of combat in the Verdun area later in the war, and the largest American cemetary in Europe is near there, the Meuse-Argonne American Cemetery, with over 14,000 US soldiers buried there.
I wonder what other sites might be specific to other nationalities, the Normandy beaches again for the British and Canadians, Vimy Ridge from WW1 for the Canadians, and certainly many others-
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