"The president had been persuaded by arguments from senior officials, including Secretary of State Marco Rubio, who said that if the United States tried to back the opposition, it could further destabilize the country and require a more robust military presence inside the country. A classified C.I.A. intelligence analysis reflected that view, as well, according to a person familiar with the document.

For Mr. Trump, the focus in Venezuela is oil, not promoting democracy.

And even though Ms. Machado has gone out of her way to please Mr. Trump, in reality her relationship with the White House had been fraying for months. Senior U.S. officials had grown frustrated with her assessments of Mr. Maduro’s strength, feeling that she provided inaccurate reports that he was weak and on the verge of collapse. They also grew skeptical of her ability to seize power in Venezuela."

(http://www.autoadmit.com/thread.php?thread_id=5817853&forum_id=2Reputation#49565916)