European countries are often said to be hesitant to challenge Vladimir Putin because of their economic ties to Russia. This is true, but those ties are a two-way street — it's because they exist that European sanctions against Russia sting much harder than similar American measures.
Here's the one fact you need to know to understand where the real balance of power lies: Russia's top trading partner is the European Union, but the EU's top trading partner is the United States followed by China.
In other words, the 306 billion euro trading relationship is a big deal either way you slice it, but it's fundamentally a bigger deal for Russia than it is for Europe:
Not only is the trading relationship more valuable to Russia than to the European Union, the EU has drastically more overall economic clout.
The fly in the ointment is that while Russia is a nation-state, the European Union is a confederation of separate countries. The EU has incredible clout when it speaks with one voice, but the process of deciding what to say is cumbersome and time-intensive.