1. I agree it would make a difference to some (actually a reasonably high) extent. But it is still too vast to explain just on that basis.
3. Not many. But even within those who do, the cost of treatment is far far cheaper to that in the US.
Okay, let us look at the salaries that a US hospital pays to it's, for example nursing staff and security staff. Typical salary of a nurse in a hospital is around $50K. Typical salary of a security guard in a hospital is around $45K-50K. Then you have other staff (excluding actual doctors). Salaries of all these people go into running a hospital.
Then, as an employer, hospital has to pay SSN tax, Medicare tax, Medicaid tax, FICA, Unemployment Fund tax, Payroll tax, 401K matching (if applicable).... all these are expenditures that a hospital has to incur in order to keep it's staff.
Convert the nurse salary to INR and decide whether an Indian nurse would be paid the same amount. Think if an Indian hospital would have to pay most of those taxes and charges for every employee.
All of the above inflates the operational / establishment cost of a US hospital way above and beyond the operational / establishment costs of an Indian hospital. Hence, healthcare becomes costly in US.
4. I completely agree on the need for patent protection. I have argued in favour out here. Having said that, the US needs a strong buyer who provides the balance on the other side. And if govt is spending such a lot on healthcare, I don't see why they don't negotiate better. Maybe a govt run insurance company is an option. Let me explain with an example - today, because insurance pays a large part of cost of medicine, everything sells. I don't remember the name of the drug now - but there is a cancer drug that extends life by 5-6 months. It is a heartless, but still relevant, question whether the 50k/dose for that drug would be better used in healthcare. Forget that, it is not necessary that just coz a drug is new, it is better than existing therapy. However, large pharma cos would naturally put more resources behind pushing these drugs as they are patented while existing therapy may be going off patent. With insurance paying for most of it, no one really bothers. Some subtle bargaining by the buyers would help rein in excesses. Anyway, that is a different debate altogether.
I would be very skeptical of a govt run insurance. See, govt provides Medicare insurance, and what does it do? It negotiates by limiting the reimbursements it gives to doctors and pharmacies. What is the result of that? Walgreens - the largest drugstore in US - is now slowly refusing to take medicare/medicaid prescriptions because it says it will incur losses on filling those prescriptions because govt reimbursements are extremely low. Similarly, a huge number of doctors in US are now refusing to take medicare patients for the very same reason - increasingly low reimbursements by govt. The point is that govt has only one way of negotiating -- decrease the reimbursements. When that happens, businesses stop accepting govt options. Ultimately, it is the users of govt options who end up becoming the losers in this entire process.
For your example, I agree, just because there is a new drug, it does not mean it is better than existing remedies. But whether to prescribe the new drug or not, in the first place, is a decision of the doctor or doctor/patient discussion. So, while insurance companies may push their new drugs, it is up to the consumer to buy it and doctor to honestly analyze and decide if it is worth prescribing. Also, if a patient can buy the 50k/dose drug then why shouldn't they?