"A lot of people didn't think we were ever going to last," King said. "Are we winning? The game is not winning in this country if we keep doing it the way we've done it forever."
The Hall of Fame player is 70 now, but hardly mellowing as a result. There is too much to do and too many freedoms to protect and too many people standing in the way.
King has crossed the point in her personal biography at which she would have been remembered primarily as an athlete. Instead, she has become an agent of change. She is a tennis rebel who wants to move the focus of the game from the country clubs to the city parks and put a racket into the hands of every child who wants one. She is a woman who has fought more than 40 years for gender equality. She is an openly gay advocate hoping to end prejudice regarding all sexual orientation.
"I had an epiphany when I was quite young that if I was lucky enough, I might have a platform and be able to spend the rest of my life trying to get equal rights and opportunities for girls and boys," King said. "That's really the WTT philosophy on life. Everyone is on the same team. When a child comes out to watch, they see men and women cooperate. Sometimes one is in a leadership role. Sometimes in a supportive role. That's really important for them to see those roles."
Some things have changed in 40 years, but not enough for King. She went to the Sochi Olympics as part of President Obama's official delegation and came back horrified by the treatment of gays in Russia. She sees the disparity in pay for men and women in this country and knows that will take decades to level out, if it ever happens. The two lightning-rod issues of her public life are among the toughest to sort out and effect change. Sometimes they even collide.
"Brittney Griner came out, and it wasn't a story. Two weeks later, Jason Collins came out, and it was a big story. It's always a bigger story when males do something vs. when females do something," King said. "Men's sports gets more attention than women's sports. Men get more attention, period."
King wonders how Michael Sam, the openly gay football player drafted by St. Louis, will do in the NFL. She understands the uproar from some quarters when Sam kissed his boyfriend on television after getting drafted and knows the day of no uproar is many years away.
"I'll be gone a long time by then," King said. "I was surprised they kissed so much, but it was totally appropriate. People just aren't used to seeing it. I'd rather see love than something else."
This season, for the first time in years, King is going to be at every Freedoms match, home and away, traveling with the team and sitting on the sideline as an assistant coach. She missed that aspect of it, and, well, she's 70.
" Fun isn't the operative word, but it is fun to get the most out of the team," she said. "My philosophy as a coach is to ask a lot of questions. Usually the first question I ask is, 'Why do you play tennis?' "
She played because she loved the game from the first time she was handed a racket at 11 years old. She still loves it and wants it to be better. She feels the same way about the country and the world. If someone would just let her make the decisions, she'd pick the right ones. That hasn't happened yet, though.
"I have to remind myself to stay on my side of the net. Just play one ball at a time," King said. "That's how you win."