As early as 1993, Russia openly claimed Sevastopol in Crimea to be a Russian city, sought to return Crimea under its control, and refused to recognize Ukrainian borders. The US leadership at that time clearly saw this but still pushed towards nuclear disarmament of Ukraine
From: Euromaiden Press BY BOHDAN BEN
When the US was conducting final negotiations with Russia regarding nuclear disarmament of Ukraine in 1994, Russia was already beginning its war against Chechnya and preparing annexation of Crimea — the latter stopped only by the timely deployment of Ukrainian forces. The US regarded Russian “interests in its near abroad” as “legitimate” and, as US Deputy Secretary of State Nelson Strobridge Talbott admitted, “shut down” Ukrainian President Leonid Kravchuk‘s pleas for genuine security guarantees in exchange for nuclear disarmament.
“The West has failed to adequately respond to the resurgence of Russian hegemony.”
“Why did America not help us in 1933?”
“Ukraine must rely only on its own forces for its defenses.”
These were the arguments spoken in the Ukrainian Parliament in 1994 before ratification of the Treaty on the Non-proliferation of Nuclear Weapons on 16 November 1994. Citizens were consulted on the issue by the Advisory Council of the Ukrainian Parliament.
Voice of Ukraine 