The benefit of ideological reasoning is that it is very convincing to those who share in the ideology. Ideological reasoning starts from axioms, or first principles, and uses deductive reasoning from there. Assuming that people accept the validity of the axioms, it will be easy to persuade them of the truth of your conclusions.
The major risk with this sort of thinking is the flip side of its strength. This sort of reasoning does not seek to persuade those who do not believe in its axioms to begin with. For example, if you believed in the importance of the rights of all human beings, you could make an argument (based on that belief) that says China should allow more freedom of speech to its people. However, this will not convince anyone who does not already believe that human rights are important.