@fBoyle-- There are degrees of being liberal. I think the US falls somewhere in between liberal and moderately liberal. There are some countries that have more liberal economies than us, but there are many countries that are less liberal. For example, European Union countries' economies are not as liberal as ours. France is only moderately liberal.
There is an organization that does research on this and puts out an index annually. So this information changes every year. Some years, our economy is considered less liberal, and on others, more. When there is an economic crisis one year, the government has to intervene more than usual and we get a lower rating on the index that year.
I guess what I'm trying to say is that this is all kind of subjective.