Why do you think harrriet tubman has the greatest impact on American history? Just need two sentences

Harriet Tubman is perhaps the most well-known of all the Underground Railroad's "conductors." During a ten-year span she made 19 trips into the South and escorted over 300 slaves to freedom. And, as she once proudly pointed out to Frederick Douglass, in all of her journeys she "never lost a single passenger."

Explanation: if need more i can add

might be agreeing to participate ethically with other european nations in the slave trade

or notifying other european nations when taking possession   of african territories

b. second continental congress