Just stuff I found poking around the web.
There might not be an immediate role for the combat brigade teams, but so much of what the rest of the Army provides makes operations by the other services possible.
But I’d like to swipe a comment from that post that I think gets to the core of what the Army provides outside of merely pumping BCTs:
As far as #2 goes, although it’s a fair point to say that the Army’s “joint sustenance” mission is dependent on sea and air power, we should also recognize that sea and air power are in many ways dependent on the Army’s “joint sustenance” mission. After all, the Army still provides the backbone of theater logistics, signals, engineering, force protection, and other critical combat service support functions for the joint force, especially overseas. These sorts of bedrock capabilities are in many ways the Army’s most important contribution to US military effectiveness, and their continued operation is essential for the projection of American power on land, sea, and air.