Peer competitors: I'm glad we agree that USA and CSA were "peers" in 61 and 62. Agree that the Yankees brought population and industry to bear by 63 and they were no longer "peers" - the Gettysburg campaign in the East and Vicksburg campaign in the West are, I think, indicative of that. My sense of "peer competitor" is really at the beginning of the conflict and to some extent the perception of the combatants but not entirely. For example, in 1845 the US and Mexico perceived each other as peer competitors - they weren't, it was just a misperception. But I do think that, as you said, in 61 and 62 the USA and CSA were.

Crimea as a "major" war: Yes, there were more theaters than just the central one in and around the Black Sea. But the Baltic theater was almost entirely limited naval action as was the Pacific coupled with a few amphibious raids. Nothing really decisive happened outside the Black Sea/Crimea theater. By contrast, the American Civil War had two major land theaters and an extraordinarily difficult supporting sea war - blockading the entire American East and Gulf Coasts (from the MD/VA border to TX). The Western theater involved cutting the Confederacy in two at the Mississippi River depriving the Confederate heartland of its Western food resources and LOC from Mexico. The eastern theater is more well known. But it was from the West that Sherman, with Grant's support and Lincoln's approval, launched his biltzkrieg from Atlanta to Savannah and then north through the Carolinas while Grant drove on Richmond all over the ground of the 62 Peninsula campaign in a giant strategic pincer.

Must be your old Tory ancestors trying to tweak this Yankee Doodle

Cheers

JohnT