"[W]ere Russia to use force against the alliance by taking a small portion of land in, for instance, eastern Latvia, EFP forces, which are based far from the Russian border, might arrive too late to engage in combat (especially given that NATO’s decisionmaking process could be quite slow). Consequently, Russia might hope to get away with a military fait accompli.

To ensure the trip wire is pulled in a conflict, NATO should ask Washington to deploy a U.S. Army battalion, split equally among the three EFP deployments in the Baltic states and tasked with continuously patrolling and monitoring borders with Russia. Yet, to maintain alliance unity, NATO should avoid additional large-scale force deployments to the Baltics.

NATO must encourage civilian resilience measures to deny Russia the ability to escalate through nonkinetic operations, perhaps by making resilience-building expenditures count toward NATO members’ 2 percent goal for defense spending.

Allies must counter Russian propaganda and disinformation targeted at Russian minorities in the Baltic states. The alliance should consider a joint NATO/EU fund for financing Russian-language media outlets, journalists, and social media accounts.

NATO members should closely monitor the state of integration and representation of the Russian minorities in the Baltic states, perhaps through a reporting mechanism."

https://carnegieendowment.org/2018/03/28/preventing-escalation-in-baltics-nato-playbook-pub-75878