“We currently have 3000 tanks in storage.”
Why do we have 3000 tanks in storage? We have them in case your fondest wish comes true and Russia attacks NATO. Then we’re going to need them. Are we supposed to strip our stocks for Ukraine and then have none when we really need them?
3000+ relatively obsolete tanks are best placed in Europe now, for possible immediate use by NATO, or transfer by NATO to Ukraine.
Every Russian tank or soldier eliminated in Ukraine now is one less that NATO will likely have to destroy. This point should go without saying, but apparently it bears repeating.
They are for short-medium term contingencies at this point. Short term 1-3 years, mid 4-6 years. After that we are probably dealing with an entirely different technological situation.
The US forces that could use them dont exist now, even in cadre, and it would be a long term, 6-10 years, before a conscripted US Army can be created on a peacetime basis. And at that point we are (as above) looking at a very different technological situation.