Total U.S. employment did peak in March 2001, but it peaked nine months earlier (June 2000) — on Clinton's watch — in the industrial Midwest. The author makes unneeded concessions. It would take a real hard nosed person to blame decline in employment on a President which started during the second month of their term. I suspect that it takes 6 months for any administration change to take effect.
Much longer than that. A president's 1st budget doesn't start until he's been in office for nearly 10 months. And much of that budget has evolved from the previous administration's budgets.