re: Planning a first trip to Paris, is it bad to go solo?

I think Paris is a great city for solo travel. It is a great city for walking/wandering, popping into random shops, bookstores, bakeries, cafes, etc while admiring the architecture and street life. It's lousy w/museums, so you can meander from one museum to another and enjoy the sights along the way.

If you're worried about dining alone, don't be. You can find cafes w/terraces so you can people watch while eating, which is a fun thing to do.

Have you picked a hotel/neighborhood for your stay? I liked the Odeon area on my last trip (around this time last year), though the Marais is always lively.

RE: American war memorials in Paris proper--there is an American cemetery in Suresnes (across the river from the Bois du Bologne). I've never been there, so no advice on whether it's easy to find, worth a visit, etc. The bulk of the US WWII stuff is closer to the coast in Normandy.