Pete Hegseth says the U.S. will no longer be the "primary guarantor of security in Europe," which he said must step up to secure Ukraine.

President Volodymyr Zelenskyy and his government in Kyiv have demanded full territorial liberation -- whether by military or diplomatic means -- per the country's internationally-recognized 1991 borders. Among Ukraine's other demands are binding Western security guarantees, ideally in the form of full NATO membership and Article Five protection.