The much-maligned "Lost Cause" narrative was part of a greater Reconciliation narrative, which was crucial to reuniting the country in strength and contributing to the healing of wounds that other civil wars have left festering for centuries. In the late 19th and early 20th centuries we came to a national consensus that the causes of both the south and north were honorable, that those who fought on both sides were deserving of honor and respect, and that ALL who fought in the war were Americans.
So things like issuing stamps to honor prominent Confederate leaders, naming military bases and warships after Confederates, and claiming Confederate heritage and traditions within the U.S. military were not seem as problematic or incongruous. It was because of this attitude that Southerners were able to embrace American patriotism, as most still do today.
Perhaps we will come to a new and different national consensus now. But we ought to be grateful that we chose the path of reconciliation when we did, imho.