Recently-resigned chief of staff to the Attorney General Kyle Sampson explains why previous presidents refrained from mid-term US Attorney purges:

“In some instances, Presidents Reagan and Clinton may have been pleased with the work of the U.S. attorneys, who, after all, they had appointed,” Kyle Sampson, former chief of staff to Attorney General Alberto Gonzales, speculated in a 2006 memo outlining Bush’s alternative approach. “In other instances, Presidents Reagan and Clinton may simply have been unwilling to commit the resources necessary to remove the U.S. attorneys.”

This is precisely why the Administration had the provision inserted into the Patriot Act which negated the necessity of Senate confirmation for US attorneys.

When, for example, Donald Rumsfeld tendered his resignation as Secretary of Defense, there were Senate confirmation hearings for replacement Robert Gates. Not only did these hearings allow the Senate to assess the merits of the new appointment, it also allowed for the Senate to engage in oversight over the Defense Department. The Senate raised issues of Defense Department operations under Rumsfeld’s tenure and questioned Gates as to his plans and priorities for the Defense Department going forward.

Moreover, the confirmation process acts as the only practical protection against the President’s use of US Attorneys for primarily political ends. When Sampson writes that Reagan and Clinton “may simply have been unwilling to commit the resources necessary to remove the U.S. attorneys,” Sampson is precisely correct. The precious resources of political capital lost during confirmation hearing for replacements would outweigh the benefit of attempting to fire independently-minded attorneys and attempting to replace them with political sycophants. Confirmation hearings would bring front-and-center the reasons for both the firings, and then close scrutinization of the replacement attorneys. These are necessary and fundamental oversight powers of the Congress.

The new Patriot Act provision allowed for an end-run around this process. Simply put, the Administration sought to insulate itself from the “resource costs” of purely political and cronyistic use of officers of the federal courts.