U.S. boards un-sanctioned tanker with Venezuelan oil to tighten blockade

The U.S. military early Saturday boarded a tanker that is not under U.S. sanctions as it shipped Venezuelan oil in hopes of escaping a blockade imposed by President Trump, according to two sources familiar with the action.Why it matters: The show of force makes it clear the Trump administration considers almost all oil tankers carrying Venezuelan crude to be subject to search and possible seizure — whether the vessel is under sanction or not.This is the second tanker carrying Venezuelan oil to be boarded by the U.S. It is unclear if the U.S. will take control of the oil as it did with the vessel Skipper, the first of its kind seized on Dec. 10. "This is a message to Maduro," one of the sources briefed on the boarding said, referring to Venezuelan strongman Nicolás Maduro, who has been indicted as a "narco-terrorist" and is wanted by the U.S.Zoom in: Six days after the seizure of the Skipper, Trump announced the blockade would apply to all vessels that are on the U.S. sanctions lists servicing Venezuela.But as Axios first reported prior to the announcement, Trump advisers believed that almost any vessel carrying Venezuelan crude would be subject to seizure.Maduro on Thursday dispatched two non-sanctioned vessels with Venezuelan oil, at least one of which was escorted by a Venezuelan naval vessel.The big picture: One of the sources briefed on the action said the decision to board the tanker was a sign that the U.S.'s unprecedented armada off Venezuela isn't for show."Even if we don't seize the oil, it's telling everyone who decides to play this game that we're going to interdict you at will," the source said. "Who is going to want to take that risk?"Go deeper: Trump escalates Venezuela standoff with oil tanker seizure