UK Forces are a political tripwire.
US more likely to come to the aid of Estonia than Latvia and Lithuania as they are the only Baltic country that now spends over 2% on defense and they also contributed to US forces in Afghanistan and took losses.
Trump imo and with his actions is owned financially by Russia and also likely with 'Kompromat' through his visits to Russia from the late 1980's onward. Russia might have 'their man' in the White House through the use of 'Active Measures' during the presidential election, but the US system of government means that Trumps powers are quite limited, as planned by the US founding fathers, and Russia does not own the GOP in Congress and the Senate where it is business as usual. It may well prove to be a Pyrrhic victory for Putin.
Will Russia attack the Baltics? Unlikely, as the risks v gain doesn't make any sense to me. Much more likely is an invasion of Belarus, where their dictator is often at odds with Putin, and had gone one step too far with his vagrancy tax, which is causing major unrest through demonstrations and some rioting. Kazakhstan is another more likely candidate, where Putin and their president are at political odds. For a predator like Putin it makes sense to go for the weakest targets with the biggest potential gain and with the least likely sanctions and fallout with the West.