"George F. Kennan strongly opposed NATO expansion, calling it a “strategic blunder of epic proportions” in 1996 and “the most fateful error of American policy in the entire post–Cold War era,” warning it would inflame Russian nationalism, damage Russian democracy, and revive Cold War tensions."

William Burns cable to Condeleeza Rice in 2008 (exposed by Wikileaks): MOSCOW 182 Classified By: Ambassador William J. Burns. Reasons 1.4 (b) and (d). 1. (C) Summary. Following a muted first reaction to Ukraine's intent to seek a NATO Membership Action Plan (MAP) at the Bucharest summit (ref A), Foreign Minister Lavrov and other senior officials have reiterated strong opposition, stressing that Russia would view further eastward expansion as a potential military threat. NATO enlargement, particularly to Ukraine, remains "an emotional and neuralgic" issue for Russia, but strategic policy considerations also underlie strong opposition to NATO membership for Ukraine and Georgia. In Ukraine, these include fears that the issue could potentially split the country in two, leading to violence or even, some claim, civil war, which would force Russia to decide whether to intervene. Additionally, the GOR and experts continue to claim that Ukrainian NATO membership would have a major impact on Russia's defense industry, Russian-Ukrainian family connections, and bilateral relations generally. In Georgia, the GOR fears continued instability and "provocative acts" in the separatist regions. End summary.