Lets face facts, Estonia, except for a brief period between WWI and WWII, had been part of Russia since the Russian took in from the Swedes in 1721 (It had been Swedish From 1562 to 1721, And from 1228–1562 Estonia was ruled by a loss Confederation of Teutonic Knights, Hanseatic League and Danes).
The Capital of Estonia, Tallinn to St Petersburg Russia is only 13 hours away by Ferry, ten hours by rail and 5-7 hours by bus. The rail line is scheduled to stop in 2008 do to the fact Russia has cheap diesel fuel for buses than any other factor.
For Ferry information:
http://www.waytorussia.net/news/2004-04/ferry-st-pete.htmlFor Rail and Bus information:
http://en.wikipedia.org/wiki/Rail_transport_in_EstoniaBasically the Estonia Border is only 80 miles from St Petersburg, about the same as the Finish Border, but Finland is NOT a member of NATO and refused to Join NATO during the Cold War for the Finns knew all it would do is make the Russians Mad (and thus Finland stayed Neutral during the Cold War, refusing to permit any NATO activities in its borders, acting like a good friend of the Soviets and today the Russians.
For a comparison, The Louisiana-Texas border is almost 120 miles away from the Mississippi, yet the US in the 1830s thought that was to close and encouraged Texas to declare their Independence from Mexico and them annexed Texas, Knowing it would be war with Mexico. 80 miles is just one to two days force march, it is to close for comfort.
Furthermore both Finland and Estonia border the only sea exit from St Petersburg. Both had been used by the Swedes to invade Russia (in the early 1700s). Russia can not and will not permit any non Russia or Non native troops in any of the Baltic Countries (And Finland).
Simply put, Russia will always have a say in what occurs in any of the Baltic Countries (and I include Finland among the "Baltics" nations) and the Baltics better get use to it. Like Canada and the US, Canada will NOT do anything that the US strongly oppose, even if it benefits Canada. The same with the Baltics, Russia can take the Baltics over as quickly today as Stalin did in 1940. NATO may protest but I doubt will send in Troops (Especially if Russia cuts off Germany's access to Natural Gas). Thus my comment, Estonia is as much a part of Russia as it has ever been. Estonia is technically independent, and as long as that poses no threat to Russia, Russia has no need to end it (just like the US has tolerated Canadian Independence since 1867), but if something occurs in Estonia that the Russian strongly do NOT want, the Russians will invade (i.e. if Estonia permits non-Estonian NATO troops in Estonia). Estonia is to near, and Russia is to big, for Estonia to be truly Independent, the only real question is the relationship between Russia and the Baltics and it has to be one that the Baltics must, to a degree, act in the best interest of Russia.