Undoubtedly, there are some (few) legislators who actually intend to serve the interests of their constituents and the nation as well. However, the attractions of Congress include prestige (some people still respect those who have succeeded in getting elected to the House or the Senate), and opportunities for grafting. For example, if I have a contracting company competent to do highway maintenance, and my brother-in-law owns a car dealership, then if my congressman (or -woman) can effect a deal which gets me a contract from the highway trust fund, then my brother-in-law will give the congressman or -woman sweetheart deals on the purchase of new cars for him or her and his or her family. Additionally, lobbying firms will offer employment, or secure employment elsewhere, for a former member of Congress who has "played ball" with them. The most egregious example of this (that we know of) was the
Koreagate scandal in 1976. That was the Democrats, but don't kid yourself that the Republicans are simon pure.
In fact, the Republicans have taken this to a new level with their tax bill. Even running for a mere seat in the House has become prohibitively expensive, and members of Congress rely on donations, as well as advertising support from political action committees to get elected and re-elected. The tax bill is intended to buy that support, and to hamstring the Democrats even if they take over Congress in the mid-term election. The power of incumbency is greatest in the House, so it is doubtful that the Democrats can take over the House in 2018--but not impossible. But even if the Democrats take over both houses, there's no way they'll have the necessary two-thirds needed to override a presidential veto if they try to repeal this tax bill.
It
is sickening, and it's the worst case of that special style of corruption known as grafting that I've seen in my lifetime.