Corruption is good from the perspective of the politicians, special interests and lobbyists.
In this regard, it needs to be acknowledged that virtually every voter has a stake to some extent in one or more "special interests" and benefits to some extent from the "special interest" being successful in its little niche of the universe of governmental legislation and regulation. For example, voters are employees and they benefit to some extent if their company or industry is favored by laws that are enacted or regulations that are promulgated.
These benefits that voters get when their special interests get taken care of by the lawmakers and regulators need to be viewed in context of the great cost to us all when government penetrates and affects every nook and cranny of the economy and thousands of special interests expend huge sums and make huge campaign contributions and generally fight tooth and nail to do everything they can to be advantaged (or not disadvantaged) by the law and regulation applicable in their niche of the legislative and regulatory universe.
If the special interests pull out all the stops, so do the lawmakers. They are continuously pulling out all the stops to get the money from the special interests that is needed to get elected, which means getting the special interest what it wants in its small niche of concern. The special interest doesn't care what the lawmaker does for other special interests in the latter's respective niches of the legislative and regulatory domain. The lawmaker strives mightily to tack at least something on to legislation that can be pointed out to the special interest to show that the lawmaker is doing the best he or she can for the special interest. Frequently there are other lawmakers who are at the service of special interests in competition with the first lawmaker's special interest, and legislation grows like turvy as many lawmakers seek to get things tacked on that variously cancel out, increase social costs by giving multiple competing special interests the goodies they want, and make legislation so monstrously complex that lawmakers cannot even read and understand the legislation before they vote on it.
In pulling out all the stops to get the votes to get elected, lawmakers do not hesitate to exploit and exacerbate partisan differences and magnify and distort the differences so that matters of relatively small import are blown into life and death, one side against the other side, in order to arouse the support of the voters who supported the lawmaker. This results in the diversion of unjustified amounts of time, energy and passion by the country over such matters as the recent month long brouhaha over the extension of the payroll tax deduction. In short, corruption contributes to polarization and gridlock.
This is particularly troublesome when it carries over to the conduct of foreign policy. In legislation and regulation affecting domestic matters, different citizens will be affected differently and they will desire different things in the law and regulation. In matters of foreign policy, there is much greater unity of interest of the American people. Yet the politicians will strive to find differences in foreign policy approach that they can use to keep their group of voters aroused for them and against the politicians and voters on the other side. This being done with an eye on getting votes to keep in office is despicable and can be dangerous for the country.
In the domestic arena, rational and honest public debate is impaired by reason of the need to keep the electorate divided and polarized. Corruption can adversely affect decisions the government makes in the adoption and implementation of important public policies that significantly affect the lives of citizens.
The corruption wastes taxpayer monies. Legislation that is enacted frequently is not economically sensible, is highly inefficient, and much is put into the law to satisfy special interests that results in unnecessary spending. At a baser level, corruption can result in the government procuring or subsidizing inferior goods and services.
The corruption distracts lawmakers and causes them to spend too much time taking care of the interests of their special interests and not devoting enough time to legislative matters that are important for citizens generally.
The corruption grows itself, and grows the special interest and taxpayer money that gets fed into the corruption. The more pervasive the corruption, the weaker are the forces for restraint.
The corruption makes government and the political process less transparent. The corruption entices the wrong people to seek public office with the wrong motives.
In summary, which do ordinary citizens want? Do they want to keep the corrupt system and get the benefits they get through the corrupt system, with the large social costs described above? Or are ordinary citizens willing to say, "I am willing to give up some or all of the benefits I get under the corrupt system if I can get the corrupt system materially fixed."?