I would like to make a significant difference, but I am only one person. It is difficult to imagine that one person could do something that would positively impact a large portion of the world's population. Politicians do. Scientists do. Pharmacological researchers do. Regular people do not. Regular people can help a neighbor or maybe even a neighborhood, but not thousands or millions of people.
When I think of someone who has made a difference for a large community, I think of Sylvia Lawry. She was a regular person who made a difference that is felt worldwide.