First CAUSE: We have a choice as to what type of candidate we elect. We may elect a "politician" - 1: a person experienced in the art or science of government ; especially : one actively engaged in conducting the business of a government 2 a: a person engaged in party politics as a profession b: a person primarily interested in political office for selfish or other narrow usually short-sighted reasons.
Alternatively, we may choose to elect a "statesman" - 1: one versed in the principles or art of government ; especially : one actively engaged in conducting the business of a government or in shaping its policies 2: one who exercises political leadership wisely and without narrow partisanship. (definitions - Merriam-Webster.com)
First RESULTING EFFECT: If we elect politicians, we have already lowered the governmental ethical bar. Lowering that bar will result in legislation that meets their personal aims rather than the good of the citizens. If we elect statesmen, we have not lowered the bar, we have added the wisdom that comes with the experience of successful governance or leadership, and resulting legislation will be for the common good, not for the satisfaction of personal or partisan goals. In a majority of cases in the media age we have elected politicians rather than statesman, resulting in the petty partisanship and egocentricity that now impedes the legislative process and continually lowers ethical boundaries.
Second CAUSE: Since the 1960's we have been living in a society that has preached moral relativism. Catch phrases/philosophy - "situation ethics" a "Christian" theory from Episcopal priest Joseph Fletcher - It basically states that sometimes other moral principles can be cast aside in certain situations if love is best served; this progressed to "its OK if its not hurting anyone", "if it feels good do it", "no one has the right to say they're position is right above all others", "a loving God would never punish people or limit access to heaven", "Holy Scripture is a wonderful collection of various forms of literature", "its OK to cheat (lie, steal, murder) as long as you don't get caught", "there are NO (moral) absolutes", and finally "the Constitution is a flawed document written 200+ years ago and subject to interpretation".
Second RESULTING EFFECT: We have in our Federal and local governments a majority of politicians who, among other things, believe that their job is to interpret the Constitution rather than apply its constraints when legislating. In "politico-speak" - use the constitution when its suits them as a means to support their end goals, and discard it when it does not. Why do they feel the freedom to do this? First, there are no moral absolutes, so their are no limits to what they feel the freedom to do. Second, the governing ideas in the Constitution were based on, among other documents and writings, the moral tenets and principles found in Holy Scripture. Holy Scripture, the Old and New Testament, was for most of our founders their daily guidebook for a civil and moral life. Their success in those lives caused them to believe that the same principals would aide us in having a civil society.
If politicians no longer believe in the infallibility of scripture or that it was a Divine revelation given by our Creator so we would know how to exercise our inalienable rights, then by default they also are free to question the validity of the Constitution that was based on those scriptural principals. In short, if they believe the 2000 year old document is fallible, then by default the 200 year old document based on it is also fallible. Ergo, they may apply it situationally. In the broader picture, they can live their lives and make moral choices with impunity because their belief in fallible scripture results in no moral absolutes to govern their personal conduct.
We should not be surprised at where we now stand. We have allowed politicians rather than statesman increasing control over our nation and our lives. They are arguing rather than talking because they have their own interests at heart, rather than ours. Therefore there is very little constructive dialogue. We have compromised our own ethics and standards when convenient. We have placed our own faith in a box that says use when necessary.
When we have the courage to actually elect leaders with strong moral compass and their eyes on the future of this country and the true greater good rather than his own career ladder, we will have a chance to continue being an exceptional nation. Until then we are just tilting at windmills.