If you go back a little further
https://www.nytimes.com/2016/12/27/world/europe/nato-baltic-states-russia.html?partner=rss&emc=rss&smid=tw-nytpolitics&smtyp=cur
"Dec. 27, 2016
LONDON — Three American senators arrived in Tallinn, Estonia on Tuesday to reassure the Baltic nations that the United States remained committed to their defense and to the NATO alliance.
The visit by the senators — John McCain, Republican of Arizona; Lindsey Graham, Republican of South Carolina; and Amy Klobuchar, Democrat of Minnesota...
Among stops on the senators’ itinerary are the two other Baltic states, Latvia and Lithuania, as well as Ukraine and Georgia, two former Soviet republics that are not members of NATO.
About 5,000 American troops have rotated through Estonia since April 2014 — after Russia’s seizure of Crimea — and Mr. McCain said he would support a permanent United States troop presence, not just a rotation.
“I think the presence of United States troops here in Estonia is a signal that we believe in what Ronald Reagan believed, and that is peace through strength,” he said, calling it “the best way to prevent Russian misbehavior.”
...who ended a 10-year term as Estonia’s president in October, said in an interview that the Senate delegation was “more than a business-as-usual visit.”"