The U.S. continuously maintains and upgrades their equipment. For decades, Russia has stockpiled weapons, the components of which were stolen and sold off by corrupt officials. The scale of the corruption is impressive. One commander sold the propellers from his ship as scrap metal. On paper, Russia has still has thousands of spare tanks. The reality is a lot of them have no engines, no turrets and may have trees growing through them. Some of the tanks sent to Ukraine are from the 50s and 60s, even though they should have plenty more T-72s from the 70s and 80s. Further, they can't supply their troops because they can't maintain air superiority and their supply convoys and depots keep spontaneously exploding.
Literally, their initial push into Ukraine was halted in part because their trucks had full tanks of gas and the soldiers thought it was just a local training exercise and they wouldn't need that much fuel, so they sold it to locals for alcohol.
This is a s**tshow for Russia. The only thing they have in their back pocket is threats of nuclear weapons.
But here again, what if those weapons were as well-maintained as the rest? What happens when you try to set off a nuclear warhead that hasn't been touched in 40 years? Does anybody know?
Russia has lots of people. Cannon fodder. They won WW2 by throwing soldiers at nazis early in the war until the nazis ran out of bullets. It gave them time to develop and produce more weapons, like the T34-85 tank. Russia is no longer a leader in tank design, and now they are struggling to convince the population that they need to be the new generation of cannon fodder until they can get their act together again.
For some good, bite-sized insights into the equipment and tactics of this war, I recommend following Ryan McBeth on YouTube, especially his "Shorts". He's a former US Army veteran and very good at explaining what's going on and why. He also debunks a lot of media reports.
