If it comes to fisticuffs with the Russian side of the border, what makes you think the railroad would survive for more than 1/2 hour? The Russians keep trying to fix the railroads feeding the Ukrainian front, and the Ukrainians keeps wrecking them. The Russians have a lot more alternative routes toward Ukraine than one main line through the Baltics, so it's harder to shut them all off and keep them down, but the hits just keep on coming. So yes, the RR is a great idea as an economic and general transportation asset, and will connect the Baltics to Europe much better than present options. It's certainly a strategic asset. But as a tactical military asset it is fundamentally ephemeral.