Mike Pence says preserving conservative principles amid rising GOP populism is the calling of his life, ahead of his new book on the conservative agenda.

President Trump on Saturday threatened to "obliterate" Iran's power plants if it doesn't reopen the Strait of Hormuz within the next two days. Trump's warning comes one day after he hinted that the U.S. was "winding down" its military operation in Iran, claiming the U.S. was "getting very close" to achieving its objective. "If Iran...