Vaccine mandates will just be the beginning of the Left’s tyrannical control. If they are successful with these things, they will effectively give the Left license to do anything they want with our bodies (in the name of public health). The Left would be able to contrive any public emergency they want, have mainstream media back them up, then do whatever they want to us. Further, if the Left move American society to a collectivist mindset, they would be able to get away with atrocities as big as genocide, as they would at some point be able to say, that some in society will have to be sacrificed, for the greater good.
In addition to above, if the Left get away with vaccine mandates, they will create on top of it, a social credit score system, like what American big tech helped China build, which will regulate all our activities, depending on how we behave in the eyes of the state. For example, if we do things the Democrat party disagrees with, it will be harder for us to buy houses, buy cars, go away on vacations, etc.
After the development of the above system, the Left will migrate the system into implantable chips, with which we will need to buy and sell things. So eventually we will end up with chips that monitor everything we do, the detailed functioning of our bodies, as well as allow us to buy and sell things. These chips will probably also be releasing chemicals into our bodies, and we would be completely controlled by the government. (This is end-of-days, mark-of-the-beast, stuff.)