It would be a lot weaker not importing the oil and gas and having a significant shortage in your own country. Even worse if things escalated and they entered a war unable to have sufficient fuels and oils to run an offensive.
US really have their hands tied. Internationally, they need China to condemn the invasion, otherwise if they send troops to Ukraine it will legitimise China's entrance into a war that will escalate into a world war.
Next either one of three things will happen:
1) If the USA stations troops in the Ukraine, China will attack Taiwan forcing the allies to defend its island chain into the pacific. Russia after Ukraine will move onto Poland forcing them to fight on two fronts.
2) China attacks Taiwan before allies station troops in Ukraine, The US mobilises troops to defend along the pacific island chain, India will join the allies to attack along the Nepalise border into china forcing them to defend multiple fronts. If the are then able to force china to surrender, they will fight Russia along the Mongolian border as well as on the western front.
3) China will condemn the attacks, India will support Russia, they will take Ukraine - NATO troops will be sent to neighbouring countries to stop expansion and Russia will continue with sanctions for the next few years. The idea of war will fizzle out.
Domestically the US don't yet have support for a war on foreign lands so the threat of them entering prematurely is quite low. Also despite common thought the US generally enters wars late (WW1&2)
Honestly, Poland would absolutely and unequivocally feed it to Russia.... hell if Ukraine can grind them into the mud with old soviet tech, Mlaws and Javelins , the French have tech that would entirely bend the Russians over themselves.
Putin attacked the reactors to display his willing, his lack of fortitude and standing down shows it was but a display to improve his hand at the negotiation table. He needs to save face, and in a hurry. To get out of Ukraine, he will need more territory, and from what I can tell, the world playing proxy in this theatre, they are hell bent on sending him home with his tail between his legs. More underpowered than Superpower.
China, where do we start... communist workforce, playing capitalist games on the world stage. Lacks the innovation to bring progress to the market, currently playing the part of lowly replicator of poor quality goods. They only want Taiwan for the advanced semi-conductor tech, they see automation coming, they need an advantage. Forget the Imperialist spiel, this is about emerging markets, and trying to lock down technical capabilities to take the next step. Spent the last few decades eroding the international manufacturing sector with cheap and thus replaceable parts.... They yearn to be the Japan, South Korea, respected with industry, the steelworks of Japan, the Hyundais and Samsungs of South Korea.... Tell me the great car tech out of the brain child of 1Bn people, or the Chinese equivalent of Samsung? (Great Wall? HTC? both cloning tech and falling behind in quality, already gapped). Russia initially flexing China was balls deep backing them, world cripples their economy with a vote, Jinping denounces immediately. Best way to pay back international debt is in a dollar that depreciates 10 fold overnight. China holds alot of International debt.
Russia was due, China was warned...
Doesnt take much of a thug to pull a gun on someone and demand their purse... takes a different monster altogether to pop off if she refuses to hand it over.