All Ukrainian politicians are dependent on Washington because they save their money in Western bank accounts that Washington has influence on. Petro Poroshenko was an ideal Ukrainian presidential candidate for the US until his military provocation in the Kerch Strait. He was a guarantee for the US that Ukraine could not make any agreements with Vladimir Putin because the latter was not in position to negotiate with Poroshenko. However, on his anti-Russia path, Poroshenko tried so hard that he began leading the US to direct military confrontation with Russia. American politicians cannot afford to cross this red line and they will kill anyone who attempts to push them into war with Russia. Poroshenko’s arranged military provocation in the Kerch Strait shaped his political future.
Ukraine is a sovereign state. The EU and US do not control Ukraine. A bilateral treaty between Russia and Ukraine, signed in 2003 and ratified by Russia in 2004, governs the use of the Kerch Strait and the Sea of Azov, which in the treaty are considered to be the “internal waters” of both Russia and Ukraine.