What was decided was that the Federal Government has a constitutional right to pass legislation that regulates the health care industry.
That you focus on the mandate but are apparently unaware that health care plans are now subject to price and profit regulations reveals a rather significant lack of understanding of the scope of the Affordable Care Act.
As to the draconian new tax you refer to is a whopping $ 95 or 1 %.
https://www.healthcare.gov/what-if-someone-doesnt-have-health-coverage-in-2014/
Those that have lower incomes will be eligible for subsidies. If you want higher subsidies and public options then vote for a more liberal congress.
You are also incorrect as to 'forcing to buy from private companies' as the health care exchanges will have non profit providers as well:
http://www.huffingtonpost.com/2012/09/24/best-health-care-brands-are-nonprofit_n_1910733.html
As to the question of 'adding a new tax', this right wing meme is also incorrect. Currently hospitals are required to cover indigent care but allowed to ramp up their expenses to cover it. That is in fact a hidden tax. They will no longer be able to do so. As a result the hidden tax in inflated hospital fees will now be offset by more people joining and drastically reducing indigent care.
But back to the initial point. The President crafted legislation that would not only pass Congress and the Senate but pass the Supreme Court. Presidents since Teddy Roosevelt have been talking about this but now for the first time in 80 years it has passed. Except for England where universal care came after the war when their medical system was decimated and needed to be rebuilt, other developed countries, like Canada started on the road to Universal Single Payer Care with small steps. In Canada it started with a hospital only plan in one province. That expanded in scope and then in provinces. It took 14 years to reach universal single payer status. Our first step, by comparison, was a much bolder step. Future steps will be determined by how we control the House of Representatives, not who the President is.