The thing is, the tanks would have to get there. Getting a tank 1000 km past at least 3 unfriendly borders is an enormous logistics issue, and a major resource drain - resources that simply did not exist, not even talking about the human resources.
And you're discounting the strength of millions of super-angry people too much. They would destroy the few tanks with rocks (or molotovs, as illustrated in Ukraine) if they had to.
And you're discounting the strength of millions of super-angry people too much. They would destroy the few tanks with rocks (or molotovs, as illustrated in Ukraine) if they had to.