Potter Stewart

“ All it has done is to exercise its undoubted power to contract and to acquire title to the property, the consequent effect of which is to render the liens unenforceable because of the independent principle of sovereign immunity. The very nature of the doctrine of sovereign immunity precludes regarding its interposition as a Fifth Amendment 'taking.' It seems to me that a Court which, having established this immunity, then declares that the Government must pay for exercising it, is effectively negativing it. ”