Does hacking evidence justify new Russian sanctions?

Sixteen US intelligence agencies are said to agree it was Russia that hacked into Democratic National Committee computers in an effort to influence last year's election. Republican Senator John McCain has accused Vladimir Putin of "an act of war." President Obama has imposed new sanctions. But President-Elect Trump has been skeptical, and Sam Biddle says the public just hasn't been shown enough evidence. He writes for The Intercept, the online publication, founded by Glenn Greenwald and dedicated to transparency in government.