We did not have a treaty with Ukraine and they were never an ally.
They are not in NATO either.
UKRAINE IS OFICIALLY AMERICA’S ALLY: SIGNATURE
United States-Ukraine Charter on Strategic Partnership
Bureau of European and Eurasian Affairs
Washington, DC
December 19, 2008
https://ua.usembassy.gov/our-relationship/u-s-ukraine-charter-strategic-partnership/
Section I: Principles of Cooperation
This Charter is based on core principles and beliefs shared by both sides:
Support for each other’s sovereignty, independence, territorial integrity and inviolability of borders constitutes the foundation of our bilateral relations.
Preamble
The United States of America and Ukraine:
Affirm the importance of our relationship as friends and strategic partners. We intend to deepen our partnership to the benefit of both nations and expand our cooperation across a broad spectrum of mutual priorities.
Emphasize that this cooperation between our two democracies is based on shared values and interests. These include expanding democracy and economic freedom, protecting security and territorial integrity, strengthening the rule of law, and supporting innovation and technological advances.
Stress our mutual desire to strengthen our relationship across the economic, political, diplomatic, cultural, and security fields.
Confirm the importance of the security assurances described in the Trilateral Statement by the Presidents of the U.S., Russian Federation and Ukraine of January 14, 1994, and the Budapest Memorandum on Security Assurances in connection with Ukraine’s accession to the Treaty on the Non-Proliferation of Nuclear Weapons of December 5, 1994.
Affirm the Priorities for U.S.-Ukraine Cooperation (Road Map) signed on March 31, 2008 and the commitments to a strategic partnership made by Presidents Bush and Yushchenko on April 4, 2005.
Section I: Principles of Cooperation...
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