Nation

Follow PBS NewsHour’s complete coverage of U.S. news, reports and analysis.

President Barack Obama has rejected TransCanada's application to build the controversial Keystone XL pipeline across the United States. He said Friday that “shipping dirtier crude oil into our country” would not increase America’s energy security.

Thursday on the NewsHour, Egypt and Russia dispute the suggestion that a bomb caused a Russian jetliner crash. Also: Defense Secretary Ash Carter visits the South China Sea as tensions rise, the U.S. upgrades their nuclear arsenal, the mysterious disease…