The US is conducting a ‘witch hunt’ as during the “McCarthyism, targeting those who sympathize with Russia.
Summary
Ukraine is falling apart right now because there is no political force there that supports the idea of a united and indivisible Ukraine.
Disproof
No evidence given. All political parties and forces of Ukraine, except for the Russian-backed separatists in Donbas and Russian administration of Crimea annexed by Moscow, support the idea of a united and indivisible state.