Rep. John Lewis (D-Ga.), center, has been a tireless advocate for the National Museum of African American History and Culture. (Alex Brandon/Associated Press)

In 1988 — the year after he was sworn into Congress — civil rights leader John Lewis introduced a bill to create a national African American museum in Washington. Nothing happened. So he introduced it again the next year, then two years after that. With each new Congress, for 15 years, Lewis proposed his bill.

Lewis, now 76, is nothing if not a patient man.

“It’s very simple. If you believe in something and you want to see it through, you have to be persistent and consistent,” the Georgia congressman said, adding a bit of emphasis to two of the most important words in his vocabulary. “You never ever give up. You just keep believing.”

Lewis — whose patient activism was on display last week when he led a 24-hour sit-in over gun control on the House floor — will see his dream realized in 13 weeks, when he joins President Obama for the opening celebration Sept. 24.

Lewis’s dream faced many challenges, but he kept the faith. He didn’t give up when people said a separate museum for African Americans would lead other groups to seek their own. (Congress had passed legislation in 1989 authorizing the National Museum of the American Indian, and efforts continue for Latino, women’s history and immigrant museums.)

He didn’t give up when Smithsonian officials initially failed to rally behind the idea of adding a 19th museum to their complex.

He didn’t give up when Sen. Jesse Helms (R-N.C.), a staunch conservative and longtime segregationist, blocked the effort again and again.

“He was just bitterly opposed to seeing an African American museum on the Mall. It was almost like a part of his DNA,” Lewis said. A bill would gain traction in the House, but Helms would block it in the Senate, he said.

“I remember one occasion when it was very dark, like it was not going to happen,” he said. “Senator [George] Mitchell and Senator [Robert] Dole said to me, ‘John, we’re trying to get it through, but we don’t have anything to trade Jesse.’ ”

Lewis said many tried to change Helms’s mind. “I never had the opportunity to talk to him,” he said. “I think I would have been able to change him in a peaceful, nonviolent fashion.”

Lewis outlasted Helms, who did not seek reelection in 2002, and managed to find Republican allies, including J.C. Watts and Sam Brownback, who were critical to the bill’s eventual success.

There were a few more close calls. Sen. Paul Simon (D-Ill.) sponsored a bill that passed the Senate in 1992; two years later, Lewis got his through the House but couldn’t get a vote in the Senate. After that, supporters started to look at other options. Judge Robert Wilkins of the U.S. Court of Appeals for the D.C. Circuit was a public defender in the mid-’90s and one of the many private citizens supporting the museum.

“I was meeting friends in my basement every couple months, trying to strategize,” Wilkins said. “We wanted to create the museum, and if we couldn’t get support from Congress, we looked at other options.”

Wilkins, who is writing a book on the 100-year effort to create the institution (dating to African American Civil War veterans in 1915), launched a nonprofit organization called the National African American Museum and Cultural Complex to raise private money and won a grant from the District for a feasibility study.

Then God intervened, according to Kansas Gov. Brownback, who was a Republican senator at the time.

“It was divine intervention, and I say that truthfully,” Brownback recalled recently. He was praying in church one day when the idea of an African American museum came to him. He didn’t know that Lewis, in the House of Representatives, had been pushing for the same thing.

“A number of us at the time had been talking about racial reconciliation,” Brownback said. “I went back and asked staff to do some research. That’s when I found . . . that John Lewis had put in a bill for a dozen years.”

Along with Watts, a congressman from Oklahoma, they built bipartisan support. But they still couldn’t get over the problem of its location. Lewis and others fought for a spot on the Mall, a provision that proved controversial in the 1990s and was still a problem a decade later.

“I call the Mall the front porch of America. In the South, a lot of decisions were made on the front porch. People would meet on the front porch, and they would talk about everything,” Lewis said, explaining the significance of the site.

President George W. Bush signed the Lewis-Brownback bill on Dec. 16, 2003. The measure did not indicate a specific location but charged the Smithsonian’s Board of Regents to select it. It took them two years, but they chose the land adjacent to the Washington Memorial between 14th and 15th streets.

“When the doors open to the museum, and we go in, I don’t know what I’m going to do. I may shout, I may just cry,” Lewis said. “I think it will have a healing and cleansing effect on the very psyche of our country. And with what is going on right now, we need it more than ever.”