As President Trump's administration plans for a summit in Europe next month with Russia President Vladimir Putin, U.S. national-security officials tell Jonathan Swan and me that one of the most urgent issues will be Moscow's covert intrusion into American politics.

Be smart: The issue poses a significant test for Trump, who has been criticized for doing too little to respond to Russian invasions of the 2016 election. He hates talking about the subject, fearing it'll raise questions about the legitimacy of his victory. So how insistent will he be when he has his chance with Putin?

An immediate concern of top officials is Russia's efforts to interfere with the mechanics of voting and tabulation. U.S. officials have said: "Russians successfully penetrated the voter registration rolls of several U.S. states prior to the 2016 presidential election."

That's in addition to the propaganda efforts through Facebook and other tech platforms, which far exceed the methods used by other countries in foreign elections.
Director of National Intelligence Dan Coats told the Senate in February: “We expect Russia to continue using propaganda, social media, false-flag personas, sympathetic spokespeople and other means of influence to try to exacerbate social and political fissures in the United States."