Red Cloud knew this.

His refusal to sign until the forts were abandoned was a negotiating position backed by the demonstrated capacity of the resistance to continue indefinitely.

The U.S. negotiators ultimately concluded that getting the treaty signed — including with the unceded territory provision — was better than the alternatives.

They were correct in their calculation: Red Cloud did sign, the conflict in the Powder River Country subsided, and the U.S. government got several years of reduced military expenditure in the region.

Whether they understood that the same dynamic would play out again when gold was discovered in the Black Hills is unclear.