How did the US Navy get their motto?

Answer 1

According to the U.S. Naval Historical Center in Washington, there is no official motto for the U.S. Navy. However, Non Sibi Sed Patriae is often used and cited as the official motto even though it is not.

There are many other unofficial mottos associated with the Navy and Naval units as well.

U.S. Navy units

• US Navy: Paratus Et Potens ("Ready and Able"), Semper Fortis ("Always Courageous"), also Non Sibi, Sed Patriae("Not for ourselves, but for our country") are often cited as their motto. Core values: "Honor, Courage, Commitment". Recruitment motto: "Accelerate Your Life".
• Independent Corps
• Navy Supply Corps: Ready for Sea
• Navy SEALs: The only easy day was yesterday.
• Construction Battalions Seabee: Can Do!, Construimus et Batuimus ("We Have Built [Them] Up and We Have Beaten/Knocked [Them] Down"); (Unofficial Motto) Construimus, Batuimus, Bibimus! ("We build [Them] up, We beat [Them] down, [Then] We drink!")

U.S. Navy education and training

• United States Naval Academy Ex Scientia Tridens "Out of Knowledge [comes] the Trident (i.e., Sea Power)"
• Naval Nuclear Power Training Command Knowledge. Integrity. Excellence.