Tigerhawk explains

 Why they don't get it.   On 'you didn't build that':

 The very argument is disingenuous. Neither mainstream Republicans nor the Tea Party activists who drove the 2010 election are against public roads, public education, police departments, firefighters (Warren) or, even, technology spin-offs from necessary spending on national defense (Obama, re the Internet). There has been a broad national consensus around each of these for between 100 and 200 years (I am sure we all remember that Eli Whitney's invention of interchangeable parts was in the context of defense spending). To suggest otherwise is to erect and demolish a straw man -- an argument your adversary never made -- the last and worst tactic of a lawyer with a losing case.

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 Beyond the roads, cops, honest courts, and firefighters, government is an obstacle to entrepreneurs, not the helpful partner that Warren and Obama imply. Liberals, and especially President Obama, think that "business" is best represented by the Fortune 100 and its "chieftains". Most people who "built that" know otherwise, that government serves to entrench huge bureaucratic businesses at the expense of the upstarts that actually create new jobs. First, there are now so many regulations associated with being a "government contractor" that few small businesses can feast at the taxpayer's trough even if they had the political stroke to get the contract in the first place. Second, the ever larger pile of federal, state, and local regulation favors the large over the small, the mature business over the growing.

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 the most frustrating aspect of all of this to business people is that these points seem so obvious as to be self-evident, so when the chattering classes do not recognize them as such we distrust their motives and assume they are all a bunch of cynical parlor pinks. Increasingly, though, I believe that there are a great many people, especially in the educated elites, who are profoundly disconnected with the reality of commerce, and actually have very little idea how small and growing businesses struggle to create the wealth that we all need to support our prosperity. That is to America's great misfortune.