Keystone Pipeline
"Open your eyes, America, and see that water is in danger in your own backyard," a Sioux elder says.
The new president has long supported the fiercely protested oil pipelines.
It's an issue of construction jobs vs. the environment.
WHAT'S HAPPENING
Barring that, TransCanada would like a lot of money.
"An historic moment," Canada's prime minister says.
Roughly 40 percent of Democrats say they support the project.
"The Keystone XL pipeline would not serve the national interest of the United States," Obama said.
He'll be accompanied by Vice President Joe Biden and Secretary of State John Kerry.