The years 1789-1837 gave us seven of our greatest presidents; Washington, Adams, Jefferson, Madison, Monroe, Adams, Jackson. All of them are rated in the top 20.
The years 1837-60 gave us eight men that were mediocre (except Polk); Van Buren, Harrison, Tyler, Polk, Taylor, Fillmore, Pierce and Buchanan. None of these men got a second term and most were rejected by their own party.
Between Lincoln (1860-65 and rated #1) and Theodore Roosevelt (1901-1909 and rated #5) there were eight men in 36 years and most of them were poorly rated.
I have read that some believe that troubled times produce great men; that men step up to the demands made of them. The presidents during our wars would generally support that belief.
1. War of 1812 – James Madison rated #13
2. Civil War – Abraham Lincoln rated #1
3. Mexican-American War – James Polk rated #10
4. Spanish-American War – William McKinley rated #20
5. WWI – Woodrow Wilson rated #6
6. WWII – Franklin Roosevelt rated #2
7. Korean War – Harry Truman rated #7 and Dwight Eisenhower rated #8
8. Vietnam War – Lyndon Johnson rated #14 and Richard Nixon rated #32
(This tag team rating was a puzzle to me as Johnson got us deep into the war and could not get us out. Nixon got us out but took four years to do so. It appears the ratings of both were affected by domestic policies.)
9. Gulf War – George H.W. Bush rated #22
10. Iraq War – George W. Bush rated #34
History would indicate that when America faced tough times we had presidents that stepped up to the challenge. The last and existing conflict in the middle east is an exception as it does not appear to have produced a leader highly rated by scholars, liberals, conservatives or public opinion polls.
We have not had a president considered to be in the top 10 since Dwight Eisenhower (1952-1960). 10 men in 53 years. Must we have a war to get a top 10 president?