Whether the argument was rejected sub silentio or was surrendered, it was unavailable on remand. An appellate mandate does not turn a district judge into a robot, mechanically carrying out orders that become in- appropriate in light of subsequent factual discoveries or changes in the law. But the appellate decision severely limits the kinds of considerations open. Issue preclusion is not the sort of argument that justifies revision of a judgment already entered. Quite the con- trary.
Preclusion is a reason to avoid the toil of reaching an independent decision.
Once the labor has been under- taken and the decision rendered on the merits, it is too late to invoke a prior adjudication. Collateral estoppel would be an inadequate answer to our decision even if a district court were empowered to consider it. First, the formal conditions of claim preclu- sion have not been satisfied. Attorneys' fees under sec. 1988 go to the litigant, not the lawyer.