Near 100 year peace? Just off the top of my head, the Crimean War of 1853-56 (the Charge of the Light Brigade happened during it), and the French-German War of 1870-71 would be a bit of an interruption in that.
Ditz.
Korea, Vietnam, the Arab Israeli blow ups, Iraq and both our and the Soviets’ Afghan adventures won’t detract from the period from 1945 to now being called a “Pax Americana”, just as the Pax Britannica is used by historians to cover the period from 1815 to 1914. He’s saying the Pax Americana in which most of us have been born, reared, and assumed to be perpetual may finally be reaching its close. Historically speaking, when these periods end one can usually count the corpses in the millions. This time it could be billions.
The Italian Wars of Independence come to mind too for the transitional naval Battle of Lissa, between the Austrian Empire and Italy. It had wooden ships, armored ships, ramming and explosive shells.