From earlier this month...
YouTube: YouTube - Bush Reserves The Right To Repeat Katrina Failures
Washington Post Aritcle: Bush Balks at Criteria for FEMA Director - washingtonpost.com
It would seem that President Bush decided in a Signing Statement that the White House would not abide by rules set by congress that require the head of FEMA to have at least 5 years of disaster management experience. The White House contends that by setting benchmarks for appointees, the Legislative Branch is encroaching on the power of the Executive.
Now, Article II, Section 2 of the constitution gives the President the power of appointing offiicials, in consent with the Congress:
... he shall nominate, and by and with the advice and consent of the Senate, shall appoint ambassadors, other public ministers and consuls, judges of the Supreme Court, and all other officers of the United States, whose appointments are not herein otherwise provided for, and which shall be established by law: but the Congress may by law vest the appointment of such inferior officers, as they think proper, in the President alone, in the courts of law, or in the heads of departments.
So it would seem that Congress has the power to change those positions, by using the legislative process.
It also raises the question, as Bob Schieffer pointed out, why is he fighting this so close to the election? Why not wait? Why bring up the Katrina Debacle all over again?