I cannot ask of Heaven success, even for my Country, in a Cause where she should be in the wrong — Fiat Justitia, pereat Coelum — My toast would be, may our Country be always successful, but whether successful or otherwise, always right.

John Quincy Adams (1767-1848) US President (1825-29)

Letter (1816-08-01) to John Adams
    (Source)

In response to Stephen Decatur's toast (and subsequent popular catch phrase), "Our Country! In her intercourse with foreign nations may she always be in the right, but our country, right or wrong."

The Latin translates as "Let justice be done though Heaven should fall."