This whole discussion is indicative of one of the major problems with human thinking. As a species we love to classify things and define them as either this or that. It's an innate strategy for processing information and we are really, really good at it. Unfortunately, the utility of this method breaks down when you move beyond simple differentiation and attempt to apply it to complex, higher-order systems, or when a simple binary distinction fails to adequately describe a data set.
This is why no single "-ism" will ever be sufficient as the Alpha and Omega of a functional society. Is capitalism an important cornerstone of a liberal democracy? Of course. But is an unfettered, profits-over-all-else economic Darwinism built on greed as the supreme utilitarian virtue a sustainable model? Are some socialistic policies such as Social Security, programs to assist the poor, etc. beneficial to the overall health of the nation? Of course. Is a 100% socialist/Communist government antithetical to our shared ideal of individual liberty? Again, of course it is. The reality is that binary, ideological purism is great for soapbox proselytizing and feeling superior, but it fails every time in real life. The "free market is god" Gordon Gecko crowd and the Outback Steakhouse libertarians ("No rules, just right") just aren't living in the real world. Sure, capitalism, ambition, and innovation are important driving forces of progress and prosperity, but I bet most of you want clean drinking water and fair banking practices as well. Data shows that providing some level of social safety net and public education benefits society as a whole by reducing poverty, crime, healthcare costs, etc., but most people probably stop short of wanting to show up to your Government-chosen job and waiting for your weekly ration of bread and gruel.
The American society as set up in the Constitution is necessarily a blend of several different philosophies. It cannot be achieved nor maintained by adherence to a single -ism, be it capitalism, socialism, Libertarianism or Rastafarianism. Everyone wants the freedom to do what they want and make money. Well, in order to live in a society where that is possible you must accept a certain social contract. Laws, regulations, taxes, and the fact that everyone gets to say their piece as well are the costs of living in that society. You like roads to drive on, police and firemen to protect you? Those things take money. You want to not have to wear a mask to breathe when you're outside? Emissions regulations on industry is the price. Don't like JP Morgan and Goldman Sachs crashing the world economy by ripping off consumers and then giving themselves $30 million bonuses? Better have some banking regulations to put checks on unrestrained capitalism.
Anyone who is arguing from the high-horse of ideological purity is simply not having a practical discussion. You're not living in the real world and you're not helping.