The EU would like to buy American gas rather than Russian, but getting enough LNG infrastructure to replace piped gas is incredibly expensive and not something that can be built quickly.
The issue is US export infrastructure, not EU. EU already has an existing underutilized LNG import infrastructure. And, as late as 2008, the EU had plans to double the number of import terminals, but it was cheaper to buy Gazprom. And then the EU began building pipelines to the Middle East, hoping to drive down prices even more. When the world realized this, investment into LNG expansion "tanked".
Point is, the EU hardly cares where they get their gas. The buyer "would like to buy" at the lowest and the seller would like to sell at the highest. Even with LNG investment, the US couldn't beat Russia's price. A preference on who to buy from only becomes part of the equation once the seller starts acting egregiously and the conversation turn from economics to politics. The political conversation, in the form of "sanctions" is an effort to make gas from Russian more expensive than LNG imports. It may take some time for people in EU to realize their gas prices going up. When they do see the bill rise, they will blame Russia easily enough.
On the US side, simply the perception that it would be economically advantageous to ship LNG to EU may be all that is needed to spur investment in LNG export terminals. US companies have long been wanting to converting their now useless import infrastructure: http://www.houstonchronicle.co...
As usual this is all about about, as they say in Texas, "eril".