This lack of risk is exactly why prices are rationally so high. At least in other countries, they're irrationally high because people forgot about the risk of interest rate increases.
I agree that low fixed rate long term mortgages contribute to higher housing prices.
And the reason 30 year fixed rate loans are common in the U.S. is because the government (taxpayers) backstop most of the loans. Bank wouldn't be stupid enough to underwrite a 30 year loan at historically low interest rates of 3%.
