As far as I know, that “promise” was a preliminary conversation, not a legal matter.[1][2] Gorbachev did feel like the expansion was “a violation of the spirit

As far as I know, that “promise” was a preliminary conversation, not a legal matter.[1][2] Gorbachev did feel like the expansion was “a violation of the spirit of the statements and assurances,” though.[1] [1] Gorbachev: “The topic of ‘NATO expansion’ was not discussed at all” https://web.archive.org/web/20150331084405/http://rbth.com/international/2014/10/16/mikhail_gorbachev_i_am_against_all_walls_40673.html https://web.archive.org/web/20150331084405/http://rbth.com/i... [2] “The U.S.S.R. was never offered a formal guarantee on the limits of NATO expansion post-1990” https://www.rferl.org/a/nato-expansion-russia-mislead/31263602.html https://www.rferl.org/a/nato-expansion-russia-mislead/312636...