As Hillary Clinton becomes the first woman to be nominated for president by a major US political party, she has revealed perhaps the best-known weapon in her arsenal.

Actress Meryl Streep has spoken at the Democratic National Convention in Philadelphia.

Wearing a stars and stripes shirt, the 67-year-old Oscar winner told the audience: "We've got some fight left in us, don't we?"

She then proceeded to list off a number of famous women in American history.

"Deborah Samson was the first woman to take a bullet for our country - she served, disguised as a a man in George Washington's continental army - and she fought to defend a document that didn't defend her.

"When she took a blast in battle to her leg, she was afraid to reveal her secret so she took out a penknife, she dug out the musket ball and she sowed herself back up again - that's grit."

Talking about the nominee herself, Streep asked: "Hillary Clinton has taken some fire over 40 years of her fight for families and children - how does she do it?".

"Where do any of our female firsts, our path-breakers, where do they find that strength?".

"Sandra Day-O'Connor, Rosa Parks, Amelia Earhart, Harriet Tubman, Sally Ride, Shirley Chisholm, Madeleine Albright, Geraldine Ferraro, Eleanor Roosevelt - these woman share something in common: capacity of mind, fullness of heart and a burning passion for their cause."

Streep then told the audience: "Tonight...you people have made history - and you're going to make history again in November because Hillary Clinton will be our first woman president."

"She'll be the first, but she won't be the last," she added.