I've been in 42 of the 50 states, and I can guarantee that for some, "The American way of life" means to them the Mississippi way, or the Montana way or the Maine way.....while for others it just means basic freedom and opportunity.

Just read the page Alice linked to, and imagine how hard it is to get a clear answer in a country this large and populated by so many different ethnic groups for 200++ years.

The cliché was used to compare 'us' to 'them' during times of turmoil.