Listen to a reading of this article (reading by Tim Foley): During an appearance on ABC’s This Week with Jonathan Karl, Secretary of State Tony Blinken explicitly said that the US would not oppose Ukraine using US-supplied longer-range missiles to attack deep inside Russian territory, a move that Moscow
For whatever it’s worth, I don’t think this going to lead to escalation to nuclear war, at least within the next several months.
Russia is in a strong position right now, the Ukrainian offensive is a total failure going into winter, political support for continued arms shipments is cracking, and US election season is ramping up.
If Ukraine does try to use these missiles against targets in Russia, and more importantly and more unlikely if any of those attempts succeed at bypassing missile defenses and actually hitting valuable targets, I think Russia would be foolish to try to retaliate against any NATO or US targets outside Ukraine. The consequences of any such strikes would only jeopardize what’s currently looking like kind of an inevitable victory for Russia.
There’s also the strong possibility of these new US missiles being ineffective Wonder Waffles like everything else up to this point. Remember those British Storm Shadow missiles that Ukraine used to hit Crimea? A few strikes and Russia homed in on where they were all stored. One exploded Ukrainian airforce base later and there haven’t been any further Storm Shadow strikes.