Look at this again:  >>/54523/
Russia is perceived an enemy and, such as Iran, is treated as an enemy.
First and foremost a containment policy is in place, all the sanctions are part of it. This is the background for every other policy.
The US has policy options to pursue, however the possibilities are more limited than in the case of Iran.
I. Diplomatic options
1. persuasion/carrot and sticks - he promises some he threatens some - promise great deals and threaten with stronger sanctions, frankly this is the most digestible to all onlookers
2. engagement - dropping all the sticks, lifting sanctions, stop containment, reintegrating - war would stop right away since this would end Ukraine's support too - some of his voters would cheer, some in EU too, but lot would be angry, a lot would feel he betrayed Ukraine, and his ego can't have this
II. Military options
There is none that could involve direct confrontation with Russia. He won't start a nuclear war.
III. Regime change
With sanctions generated economical collapse and a Ukraine war fiasco Washington tried to spark popular revolt in Russia, initiating essentially all three options: revolution, insurgency, and coup. Sanctions failed to do that and Russia is winning the war currently. Putin is quite safe for now.
IV. Containment
I started with this, it's on.

We can conclude the US has two options really, one is openly betraying Ukraine, or pretending they can do something.