Once wars made presidents popular. Think of Washington and the Revolution, Lincoln and the Civil War, McKinley and the Spanish American War, FDR and WW II. Maybe that was because we used to win wars.
Korea ran Truman out of office. Vietnam made LBJ decide not to run. Before the Silent Coup, Nixon (who ended the war) was tarred with the Vietnam brush. With America winning once again, George the First got a bump from the 100 day Gulf One before we all read his lips. Then rounding out the results of quagmire wars George the Second after soaring in the aftermath of 9-11 ran aground on the sand bars of Iraq.