For some reason, you forget or ignore the military assistance of Western countries, which goes to Ukraine in a continuous stream. About 10 transport planes of military aid arrive daily from the USA through Poland to Ukraine. Caravans of trucks with tanks and other heavy armored vehicles are moving from Europe to Ukraine. Every day, Russia destroys part of the incoming military aid with air- and sea-based missiles at logistics hubs, but I think this is only a small part. Russia's refusal to bomb bridges and railroads sounds strange from the point of view of military logic, but Putin's strategy becomes more understandable in the context of a military special operation. Attacks on civilian infrastructure are a sign of genocide, and the genocide of Ukraine is clearly not part of Putin's plan. Therefore, do not worry about tactical nuclear strikes on the territory of Ukraine - Russia will definitely not do this. Although the provocations of Ukraine under a false flag are still possible.