The two major political orientations in American politics are conservative and progressive. But this pattern is not distinctly American - it is widespread throughout history. Late Republican Rome had their own conservative and progressive factions: the Optimates and the Populares. These orientations are persistent because they derive from basic psychological attitudes towards time.
Conservatives love what is. They delight in the present and the particular. They tend to be older than progressives. People become more conservative as they age and fall in love with the world. Conservatives in different places have little in common with each other because they want to preserve different things. Conservatism is local.
Progressives are in love with the future. Progressive thought tends to be abstract and speculative. It measures the present against its ideals and finds it wanting. At its best, progressivism is the conscience of society. At its worst, it is an overactive, guilty conscience that turns into puritanism. Young people, filled with a desire to leave a dent in the universe, tend to be progressive.
Reading these descriptions you might be tempted to pick which side is right. But this is the wrong way to go about it. These are two basic poles of the human psyche and they need each other to be whole. Every human institution is polarized in this way. Even a group of progressive activists will have its more conservative and progressive members*. Split a magnet in half and what you have is two half-sized magnets, fractally, down to the polarization of individual atoms.
It is the task of wisdom to balance these two impulses within individuals and within human institutions. Both orientations have failure modes when they are allowed to dominate.
The failure mode of conservatism is latching on too tightly to the existing arrangement of things. When conservatism is well balanced, it is the skeleton of society, defender of things worth defending. When it becomes too entrenched it calcifies the body politic. The society fails to address a building problem until it is too late and bursts forth into catastrophe.
The failure mode of progressivism is impatience. When progressives change things too quickly, they destroy pieces of the old order without regards to their value. The fragile, irreplaceable beauty of the world is sacrificed in service of some promised future utopia. Often, there is great bloodshed, such as in the French, Russian, and Chinese revolutions. Iconoclasm in its old sense - the destruction of icons - is solely an actively of progressives.
In the abstract, both suffer from impossibility. The conservative must make peace that the present cannot stay the same and the progressive that the task of eliminating evil eventually generates negative returns.
The continuum of time is split into past, present, and future and so far we have discovered political attitudes that correspond to two of the three: present -> conservative and future -> progressive. There is one other basic political orientation but it is less common: the reactionary. Reaction is in love with things past.To explain reaction and how it influences modern politics would be a large tangent that would distract from the elegant model so far developed in this post. So I will leave that for later. But a healthy psyche or good society will also balance reactionary feeling with conservative and progressive.
* Progressive movements, driven by the fuel of righteous anger, are especially tempted to purify the whole by purging more conservative members. See the infighting of the modern social justice movement, or more spectacular bloody purges of the past: