Answer:
Politics can affect and even dictate the manner in which science is done. For example, passing laws that limit whether embryos can be used in stem cell research. Politics can allocate funding to various scientific causes. Politics can create a great research environment in the universities. And so on.
In extremes, politics can even make entire areas of science off limits. In the early twentieth century, lots of very smart and decent people were eugenicists. Politics (in particular, the unbelievable moral horror that was Nazism and the Holocaust) change