Baltic countries dream about becoming an American base. Firstly, because the Americans will pay them something. Then, their hysteria about terrible Russia, which will destroy them, will weaken a little bit. And lastly, they are hoping the US will help them to take a more serious place in Europe.
The Baltic States as well as Romania, Poland and Bulgaria are NATO allies and cooperate with the US in ensuring transatlantic security. The statement of the Bucharest Nine ahead of the NATO summit in 2018 can be read here.
Baltic states are independent states. Latvia, Lithuania and Estonia have been EU members since 1 May 2004 and NATO members since 29 March 2004. As for any of the EU Member States, Baltic countries have rights and obligations. There are no serious and non-serious places in the EU.