In "Philosophy and Politics," Russell shows how philosophy and politics have informed each other in nearly every culture. For example, communist leaders in the Soviet Union relied upon Marx's philosophy of history (historical materialism) to implement their version of communism. Russell argues that since politics and philosophy inform each other, a philosopher or a politician should seek and use the best philosophical/political perspective; and that perspective should be based upon empirical (observational) evidence on how to best provide for an ethical and happy society. Subsequently, Russell argues that a government that bases its practices solely on an ideology (often an abstract ideology) is too focused on an abstract ideology, effectively ignoring real practical applications of a philosophy and/or political agenda.
Russell notes that while Hegel's (and Marx's) ideas seem scientific (based on the dialectic and both purported to be philosophers of history), those who have implemented their theories have done so with an "ends justify the means" ethos:
If you know for certain what is the purpose of the universe in relation to human life, what is going to happen, and what is good for people even if they do not think so; if you can say, as Hegel does, that his theory of history is "a result which happens to be known to me, because I have traversed the entire field" - then you will feel that no degree of coercion is too great, provided it leads to the goal.
In other words, if a person/group/country agrees with a government/autocrat/dictator simply because that government or leader claims to know what's best, then they will necessarily agree with any means by which to achieve their government's end goal. This is dangerous territory because it allows the government/leader to do anything. Not only is this dangerous; it tends to place too much importance on the big theoretical ideas, rather than addressing the real needs of the people.
This is why Russell advocates empiricism or democratic socialism because he favors a political-philosophical perspective based on the social good, will of the people, and a perspective that is scientific (empirical) rather than theoretical. Russell's approach is inductive.