There are at least three areas of potential political roadblocks to a viable space tourism business.
First of all, it should be recognized that there are some (though by no means all, or even a majority) within the U.S. government who view space (or at least the human spaceflight segment thereof) as an exclusive province of (federal) science and national security, and private-sector activities of any kind as interlopers. To those with such views, opening up this frontier to anyone who wishes to go, at costs that are affordable to the general public, rather than privileged government agencies, will be seen as at best an inconvenience and irritation, and at worst a threat to national security and (less nobly) their own bureaucratic power base.
Second, to whatever degree that this activity is actually supported by federal funding, unless it is provided via lottery, some will view it as a taxpayer subsidy to the wealthy (who, barring lotteries or contests, will initially be the only ones who can afford space trips) for their own frivolous pleasure. Even if there is no government funding involved, there is historically such a strong linkage in the mind of the public between NASA and space that any space tourism activity, even private, may still be mistakenly perceived by some as a waste of public funds. It is important, therefore, that economic gain, increased tax base, and productive employment be promoted as an inevitable byproduct of a successful space tourism business.
Finally, there is a segment of society that seeks the elusive (indeed, impossible) goal of zero risk in all activities. Relating back to the regulatory issues, there is a danger that some "public-interest" groups will attempt to impose, by lobbying for legislation or regulations, unreasonable standards on space tourism vehicles and operations.
Specifically with regard to use of the Space Shuttle for nascent space tourism activities, some within NASA will be concerned about the potential public-relations disaster of another civilian loss, as occurred in the Challenger incident. There will be specific legitimate concerns, discussed more in the section on public Shuttle rides, about interference with the mission and flight safety. In addition, many will be loathe to give up a precious seat to a non-NASA person when they have so many astronauts in the corps who have yet to fly, even though it might be in the national interest to do so.
In general, early space tourism activities will act as a pathfinder to test the political and institutional waters, and educate both the public and the various entities within the Beltway on the subject of public space travel and private space activities in general. Particularly as a number of different companies emerge, both as vehicle providers and service providers, and market their services, the current inseparability in the public mind between the government and space will gradually erode, substantially improving the prospects for both building markets and attracting investors.