It's also convenient for maintaining a grip on power and something I'm certain both parties have internally considered. Think about the most recent election. How many people voted for Hillary thinking, "I think this person truly and accurately represents my views and beliefs." And similarly for Trump? By contrast how many voted for one or the other thinking, "This person is trash... but, my god, the alternative is just completely unacceptable!"
The same sort of attitude ensures that third parties will never be considered. When people are driven to literally fear the 'opposition' winning, it means that the powers that be have effectively sealed their grip on power tight. Also even notice the media's focus on "electability." It's all rhetoric designed to get people to note vote for the candidate they want in power, but to 'strategically vote' and in the process completely undermine their own self interest.
Pair this with some institutional issues like ballot access and we have a system where the establishment has all but guaranteed their perpetual success.
The same sort of attitude ensures that third parties will never be considered. When people are driven to literally fear the 'opposition' winning, it means that the powers that be have effectively sealed their grip on power tight. Also even notice the media's focus on "electability." It's all rhetoric designed to get people to note vote for the candidate they want in power, but to 'strategically vote' and in the process completely undermine their own self interest.
Pair this with some institutional issues like ballot access and we have a system where the establishment has all but guaranteed their perpetual success.