"Politics" is the practice of influencing other people on a global, civic, or individual level.
"Art" is a diverse range of human activities and products of human activities characterized by its representation of reality, expression, communication of emotion, or other qualities.
Should politics and art be combined? I think they already are. If politics has to do with human interactions and art has to do with human activities and their outcomes, the result would simply be society itself. Many people say that politics should be all about objective reasoning and deductions while art should nothing more than indulging expression. But, that limits the human experience to a false dichotomy. Why can't art personal expressions influence politics? People are shaped by their peers and their environments and creates a unique picture of a particular society as well as the world in that specific person. An artist is born with talent, talent is shaped within them.
I guess one could make make an argument that specific individuals have a unique neural chemistry that may give them abilities that more average human beings don't have, but that doesn't mean that any individual isn't able to achieve that same level of intelligence through passionate hard work.
Regardless, individuals are shaped by their respective environments, with the strongest influences usually being family ties. While we can debate about what is "good" art all day and night, we have to acknowledge that even art we don't particularly identify with is still a representation of what that specific artist sees in the world around him. And, since politics simply refers to people interacting with each other using our own spheres of influence, art seems like a natural byproduct of that interaction.
People combine politics and art every day just by writing a story or a poem, drawing a political cartoon, or singing a song about what they enjoy about life or why they think life sucks. An artist is is trying to influence you through their art by giving you an glimpse into how they view the world, and that view of the world has been influenced by how that person grew up in their respective society.
So, . . . .
What is art? Anything. If you want to showcase your view of the world, then that creation is a work of art no matter what form of media it is being showcased in. Every person has something to say and a unique way to say it.