I highly doubt Putin is terribly worried about this.
This is hardly the first time Obama has tried to draw a line to look tough against other leaders. He has backed down before, i see little reason to think he is going to hold to his word this time. If he was a man who was going to hold to his word, he would have done so a long time before this.
Obama can only do what the EU will agree too, or he cannot get out too far ahead. But the basic thread here is that Bushii initially, and the EU, thought Russia would act like a 21st nation state in accepting Reagan/Thatcher neoliberalism with its central premise that govt may ONLY act FurtherorProtect free markets run by individuals making free choices. Bushii was disabused of that notion, in part when Russia attacked Georgia. Obama, naively, tried reapproachment, only to see Putin emerge with a cult of personality with an aim at a new Russian Empire.
The EU tied its troth to Russia's oil and gas. There's a sort of 1970s OPEC to this, with oil being used for a political purpose tied to geopolitical, rather than capitalist, aims. We did a deal with Saudis where they bought a bunch of US equities and debt, so we're joined at the hip. We have done the same with the Chinese, though nationalist tensions remain.
Imo the OP, and this thread, put too much ideological influence on individual actors and parties, and not enough on cultural distinctions. If not for Putin, the Russians would probably need a different 'man of steel.'
Curiously, Merkel is the most resistant, along with France. Merkel is a conservative with every dislike of expansionist regiemes. France is socialist, trying to hang onto its economic .... lifeline. Yet, the socialists and conservative germans are tied. They are both neoliberal economies.
Obama must be seen as weak, despite being more aggressive that Bushii ever was. But, the neocons had qwagmired us elsewhere. And Bushii and Obama are both neoliberals.
In short, I don't see this as an actual political issue, beyond partisans needing bushii or Obama to "win." Rather, I just see it as a continuation of Western culture evolving, and as Reagan would probably see as the inevitable march to individual freedom from the state.