Both systems have their pluses and minuses.
It all comes down to whether or not you believe that healthcare is an expectation or a luxury.
It is not comparing apples to apples. There are flaws in the Canadian system and flaws in the American system.
Canadian system tends to have longer waiting lines. But everyone is covered.
Americans have faster service. But 15% or so do not have health insurance.
Canadian system has been government run for over 30 years.
Switching over to a public system in the US could put even more strain on a ~$500b deficit.
The healthcare industry is the largest industry in the US (i think) and converting and restructuring would be very costly and a nightmare logistically.
There are also social issues to contend with. Per capita major crimes, car accidents, and pollution exposure is much higher in the US and will in the end cost more.
I am a supporter of two-tier healthcare. Not popular with the people in Canada but to me makes sense.
If you are rich and pay your taxes, and continue to effectively pay into the public healthcare system, i have no problems with you going to a private hospital to pay for your treatment. This not only allows the rich to avoid long lines, but the poor have one less person in front of them in line. And since the rich person is effectively paying double, the care for the poorer majority would be the same or improved.
Now it is very well known that Canada spends far less than the US on healthcare (not even taking into account the efficiencies) but in the end we are basically stuck with what we've got.
For reference:
Canada Medicare
Country / life expectancy / infant mortality / per capita cost (USD) / % GDP / % gov't revenue / % paid by gov't / % paid by private sector
Canada 79.3 / 5.6 / 2,163 / 9.5 / 16.2 / 70.8 / 29.2
USA 77.0 / 6.4 / 4,887 / 13.9 / 17.6 / 44.4 / 55.6
Canadian and American systems compared