The Equal Rights Amendment was written by Alice Paul in 1923 as the necessary second step after suffrage and achieving the right to vote in 1920," Kamala Lopez, executive director of Equal Means Equal, explained to Salon's Amanda Marcotte. "Everybody thought it was gonna be very simple, a no-brainer."

This proposed amendment to the Constitution, which would bar discrimination on the basis of sex, will be 96 years old in 2019. Instead, it's nearly forgotten to history, but Lopez is on a mission, which is building momentum under the radar, to finally make women's equality an official part of the U.S. Constitution.

They have one mission: Turn the Equal Rights Amendment into a constitutional reality. And they're a lot closer than you'd think. Lopez directed the 2016 documentary "Equal Means Equal," and Marcotte is one of the interview subjects.

"When the movie was released in 2016, we still needed three states" in order to ratify the amendment, Lopez said. "Now we only need one."

The amendment was very nearly ratified in the 1970s and 1980s, until a religious right movement, led by Phyllis Schlafly, was able to successfully scare legislators out of passing it with lies and urban myths about the supposed dangers. That struggle will be portrayed in the upcoming FX series "Mrs. America", with Cate Blanchett in the villainous role of Schlafly.

"The principle is very simple," Lopez said. "Do all people deserve equal treatment under our laws or not?" Watch the interview above to hear what the Equal Rights Amendment offers and why Lopez says it will help protect working mothers.