The real challenge to the West is not in terms of exports or technology or combat capability, but that it tests the limits of the new American strategy of regional multipolarity.
While it is quite clear that Russia does not have the resources to field, let alone manufacture, thousands of units of this platform, its unveiling pushes Western European governments closer to re-armament.
So:
A. America wants Europe to maintain its own security.
B. America does not want a volatile and highly-remilitarized Europe, either east or west.
Let me clarify point B. America wants to take the load off its shoulders, but it still wants to retain a significant amount of military influence and strategic control, especially in Europe. In other words, the implicit Russian threat is of a European arms race that limits American power throughout the continent. If the UK, France, and Germany were to step up and become significant military powers once again (though arguably the UK still has a relatively-powerful military), then European states from Iberia to the Caucasus would be less likely to rely on American military promises and posturing and instead turn inward. America, as we all know, has perceived a Europe able to act strongly outside of American will as a serious geopolitical risk for over a century.
The only alternatives, then, are calling Russia's bluff - risky, since Russia certainly isn't 100% bluffing - or the US taking the lead in European defence yet again, something that the United States has constantly wanted to avoid and is trying to orient itself away from. What I want to hear about are Western European reactions. Sure, Eastern Europe would love to have America take care of their defense, but then it all depends on how France, Germany, and the UK interpret their own roles. Maybe the old great powers will want to carve out their own spheres of influence once more...
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