Have you asked it yourself? What business does Pelosi have traipsing all over the world, costing the taxpayers millions of dollars? Name a country - she has probably been there, and on the taxpayer's dime. But why? What is her function?
She is a congressperson (1 of 435 representatives, or 535 people if you count the senate) who was elected by a relatively small number of people to represent THEM. She does not represent me, nor does she represent you if you're not in her district. Is it the function of a congressperson to travel the world at the people's expense? WHAT is she doing? What is the purpose of her visits? She is not an ambassador, she is not a negotiator. She is a congressperson from one out of hundreds of districts who represents a relatively small number of people. I never see anybody question these trips or the justification and authority behind them. It seems most Americans will put up with just about anything, without question.
You'll get a canned non-answer.