Vostok, Mercury, Gemini and Apollo was "true exploration". Those programs did test, try and enable things humans had never done before. But today, what the Space Shuttle does for example (and Soyuz as well) isn't "true exploration" anymore in the first place. STS basically is a transportation system that was meant to be commercially sucessful and self-profitable, which was the only reasoning that enabled its funding. But NASA's structure still does not enable an efficient program yet. Constellation was another example of a big epic fail. It's not because "it is always expensive". It is because of the way NASA gets and distributes money and how the whole thing works (it's a big national job keeping program and a big bureaucracy).
Commercial space flight does not mean that people directly pay companies. It means a different way of distributing the money. Of course SpaceX gets money from NASA, i.e. the government. But the difference is that SpaceX works more efficient with that money. For the development cost of Falcon 9, including Dragon (only ~370 million USD), NASA wouldn't even have managed to clean the floor inside the VAB. Of course it's ironic but we shouldn't forget that Constellation has swallowed 9 billion USD whilst there is not a single piece of an Ares 1 second stage and no Orion (beside mockups). All we've seen is animations and 3d videos. 50 more billion USD would have been required to finish the thing and make it fly whilst it would have been more costly to operate than the Shuttle (with 50% less payload capability). A lot of people still didn't realize that the way NASA works they won't return to space manned anytime soon, at least not by wasting billions whilst it could be done less costly. The world has significantly changed since the early 1970's when the Shuttle program got the go.
Not NASA, but SpaceX got the biggest commercial contract in space flight history with Iridium Communications Inc. (about 500 million USD). And again, 50% of all Russian launches are commercial launches whilst NASA does only about 6% comercial launches. NASA is in a downward spiral. And the senate isn't going to make it any better. NASA needs reforms. Reforms that will hurt a lot of people but it's necessary if NASA wants to keep a reasonable level of funding for manned access to space...
I now that I'm not making a lot of friends when I say this: the big times of big manned space programs are over. There are only two ways: more commercialisation or international partnership.
Heavier-than-air flying machines are impossible.
Lord Kelvin, president, Royal Society, 1895