"And...FDR moved HST into the vice presidency on Jan. 20, 1945, but by April 12, HST had left the vice presidency forever."
huh? So was FDR planning to die 4 months after that appointment? your comment makes zero sense.
Being the nation's AG is an *important* job, it will require another confirmation to get a replacement, it's not an easy process, etc. If Bush was 100% determined to put Gonzalez on the bench, he would have done it already.
Three consecutive attorneys generals (1972-75), Richard Kliendienst, Elliot L. Richardson, and William Saxbe, served 11 months, four months, and 13 months, respectively. It is not uncommon for attorneys general to serve short periods of time before taking other assignments.
And FDR may have well known that he would not complete his fourth term. FDR did not keep HST informed if he thought he would not remain long in the presidency. HST knew nothing about the Manhattan Project until after assuming the presidency.
The point is: Gonzales serving seven or eight months as attorney general before going to the Supreme Court would not be unusual. I hope Gonzales is NOT the choice.
The attorney general is an important job, but it did not become part of the Cabinet until 1870, when the Department of Justice was created. Early attorneys general came and went, such as future Chief Justice Roger B. Taney, brother-in-law of Francis Scott Key.