The Impeachment of Trump

Why do people want to become politicians and want to go into politics at the national level? Presumably, many years ago, people went into politics because they believed it was their civic duty to represent the people of their districts and believed they could do it well. A few decades ago that all changed. An incumbent could run on the issue of ¿look what I have done to help¿, whether they helped or not. Incumbents can claim that they are ¿climbing the ladder and if re-elected could do even more¿. Would be politicians have a difficult time overcoming those kind of statements. Political seats do not change often and thus we now have ¿professional¿ politicians, people who can and have served for decades. What could possibly go wrong with that? Professional politicians often have very different agendas, many of which are not in the best interests of their constituency.