Has there every been a us president that we did not have a war under?

probably not as the US has a great appetite for war Depends how broadly you define "war". If wars against Indian tribes, or "sending in the Marines" to Latin American states are disregarded, there were no wars under Washington, Jefferson, JQ Adams, Jackson, Van Buren, WH Harrison, Tyler, Taylor, Fillmore, Pierce, Buchanan[1], A Johnson, Grant, Hayes, Garfield, Arthur, Cleveland, B Harrison, T Roosevelt, Harding, Coolidge, Hoover, Carter, Reagan or Clinton. [1]Unless the 1857 military expedition to Utah counts as a "war".