That is all extremely simplistic. Russia at present is a bit of an oddity. People trying to compare the current Russia to the Soviets or the Tsars are just looking to condemn it as a fascist regime rather than doing any careful analysis of its political system and governing philosophy. The reason Putin can get support from radical leftists and far-right nationalists is that he has pioneered a form of left-wing nationalism that can appeal to both groups. It helps that the "far-right" itself has moved decidedly to the left over the past few decades. Of course, Fascism was ultimately a nationalist derivation of traditional left-wing ideology, so it is not too surprising that they would have some left-wing inclinations. Yet World War II eventually led to the repudiation of the more right-leaning ideology associated with Adolf Hitler in favor of the views of Gregor Strasser who was killed during the Night of the Long Knives. At the same time the far-left became increasingly nationalist due to a rejection of Soviet hegemony, itself the product of growing nationalism within the Soviet Union.
The main reason why I am so skeptical of Europe's prospects in any trade war with Russia is the issue you are talking about. Russia is strong and unified politically, economy, and socially. In contrast, the European Union is riddled with division and weakness. You have division between national political parties, between regions with the nation, and then you have the various Union-wide divisions. Europe is weak economically as we all know, politically the union is weak, and you have a broad social weakness. A product of various ill-conceived policies that made sense when they were merely a major outpost of the American front against the "communist threat", but are no longer viable in the post-Soviet order. The main result of the collapse was that the EU took on the suicidally defiant east who are, despite their obstinance, even weaker on all counts. Save for greater national pride, they have less going for them. You have the far-right, far-left, Eurosceptics, Europhiles, and various secessionist movements all mixed in with rising radical Islam in there as well.
Pressures like economic calamity or war can easily make the whole thing break apart. Given the current state of the European economy, calamity would be terribly easy to induce for any major outside power, such as Russia, and I do not expect that to be any less true in future years.