The way I'm reading, the text of the memorandum implies the USA, Great Britian, and Russia won't invade and will respect Ukraine's border, and will represent Ukrainian interests on the UN security council if they're threatened by nukes.

I don't see agreements to provide direct military intervention unless I'm missing something important.

[–] zephyreks@lemmy.ca 3 points 1 year ago

https://www.brookings.edu/events/the-budapest-memorandum-at-20-the-united-states-ukraine-and-security-assurances/

Pifer claimed that the US implicitly suggested that "lethal military assistance" was the type of support that would be provided.

Also, since all veto-holding members of the UNSC provided similar assurances, it was expected that direct UNSC peacekeeping intervention would be possible. For obvious reasons, it wasn't.