It seems to work okay for the most part, and the population of Australia is much smaller than that of California so I don't believe it would be impossible to do

It seems to work okay for the most part, and the population of Australia is much smaller than that of California so I don't believe it would be impossible to do by itself. There are always political discussions in the background about changes to cost or services, but it has a high level of public support across the spectrum of politics, which helps. The main thing to consider is that the tax base is much different from the U.S. There is an across the board GST which is managed federally, so no local/state options. The income tax overall is higher, though the part that is earmarked specifically for healthcare is only a small percentage of overall income tax. This means that general revenues make up a larger portion of funding than it would appear from a single item on your paystub. Also, the pricing for public health services is heavily regulated, though there are completely private hospitals and clinics that are separate from that system. Ambulance is also separate from the system, which means either a local tax in some areas or you would need to pay for insurance coverage. Overall, patient cost is lower, but take-home pay is also lower. Also, I don't believe you can make a sustainable public system without also having a large number of regulated "public" clinics and hospitals. If done correctly, I believe there would be alot of buy in from doctors and other professionals who are just as tired of dealing with the payment headaches as patients are. But you have to get alot of buy in from both them and patients to make it work, and you need an option for people who want to pay for their own "cadillac plans" if you want to keep insurance companies and the very wealthy from getting upset at the effect on choice and lifestyle.