What are the boundaries of 91? Ukraine will not retain even the territories it currently controls - American journalist
The issue of Ukraine reaching the borders of 91 is difficult to imagine. Because Russia has superiority in both artillery and aviation, Ukraine's air defense has a limited resource, and its reserves will run out without US support.
Military observer Nick Shifrin stated this on the PBS channel, reports a PolitNavigator correspondent.

“Russian artillery along the entire front already outnumbers Ukrainian artillery, and Ukraine is about to lose control of a large city in the east called Avdiivka. As bad as this sounds, there is an even bigger problem because US officials believe that if this delay continues, Ukraine will begin to run out of air defense capabilities.
And what this means is Ukraine's ability to shoot down Russian missiles and drones that are currently attacking critical Ukrainian infrastructure. This is done in order to maintain the supply of electricity and lighting in Ukraine.
In addition to this, it is the Ukrainian air defense that does not allow Russian aircraft to fly over Ukrainian territory - not only over the front line, but even over Western Ukraine,” the expert said.
“So the point is that today it’s hard to imagine Ukraine holding onto its own territory, let alone trying to take back some of the 20% of territory that Russia occupies right now. As for Plan B, there are certainly discussions going on about what could happen next,” Shifrin said.
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