"The proposed Keystone XL pipeline that would ship oil from Northwest Canada south through Mid-America to the Texas Gulf Coast has drawn sharp opposition from environmentalists worried about Canadian forests, greenhouse gases, and potential leaks.

But one line of attack is more about economics and geopolitics than land and water. And it strikes at pipeline proponents' central argument that Keystone XL would buttress U.S. energy security. Opponents contend instead that the pipeline's petroleum could largely bypass the American markets and be shipped to Asia. ..."

http://news.nationalgeographic.com/news/energy/2011/08/110819-keyst...

Yes, this is about oil rather then gas.  But the same situation applies to natural gas/LNG.