SANTA CLARA — Dipping into the raging debate about the lack of diversity in Silicon Valley’s workforce, Hillary Clinton told a women’s conference here Tuesday that the valley’s glass ceilings still need smashing.

The presumed Democratic presidential candidate said women are still woefully underrepresented among the valley’s executives, investors, engineers and software developers — and that they often earn less than their male counterparts.

“While nearly 60 percent of college graduates are now women, they earn only 18 percent of the computer science degrees. That’s actually less than half of what it was in the 1980s,” she said. “We’re going backwards in a field that’s supposed to be about moving forward. We cannot afford to leave all that talent sitting on the sidelines.”

Clinton remained coy about her White House aspirations but was candid about Silicon Valley’s gender gap when she spoke to about 5,000 people at the conference’s keynote luncheon.

She praised conference organizer Watermark, an organization of Bay Area executive women, for sponsoring a Stanford University class on women’s entrepreneurship. And she also gave a shout-out to Google for releasing data on the role women play in its workforce. But, she said, much more remains to be done.

“Inclusivity is more than a buzzword or a box to check,” she said. “It is a recipe for success in the 21st century.”

A report this month from Joint Venture Silicon Valley spelled out just how big of a problem the income gap is: Men with bachelor’s degrees earn nearly 61 percent more than women with the same degrees.

According to PayScale, a Seattle-based compensation software company, the top jobs for women in the valley are in marketing, sales, administration, operations and accounting. Men, PayScale says, dominate the valley’s higher-paying fields, such as software engineering, network systems analysis and computer systems management.

The issue of promotion and income inequality will take center stage in the high-profile sex discrimination trial of Ellen Pao against her former employer, Kleiner Perkins Caufield & Byers, a Silicon Valley venture capital firm. Opening arguments started Tuesday.

Clinton argued Tuesday that it’s a matter of making sure that girls have access to the same technical and professional education as boys; that there are jobs for them when they’re ready to work; that they’re paid the same for those jobs as men are; and that women have equal access to capital for starting their own businesses.

She also said a national paid-leave program is long overdue because the U.S. is one of few developed nations still lacking one. California, she added, has had one for a decade and it seems to work well.

Women, she said, also remain underrepresented in many industries across the U.S. and in countries around the world — and that’s not good for any economy or society, she said.

“Where women are included, you’re more likely to have democracy; you’re more likely to have stability and prosperity,” she said. “It’s not just a nice thing to do.”

She quoted former U.S. Secretary of State Madeleine Albright as saying “there is a special spot in hell for women who don’t help other women,” and she exhorted the women at the conference to do their part.

“There has never been a better time to be a woman in the history of the world,” she said. “But I also believe, and maybe it’s part of the American DNA, that we have a special obligation to make it better for each other and ourselves — and for women across the globe.”

Organizers declined to say how much Clinton was paid for the speech.

Clinton’s critics say she should put her money where her mouth is. She seems “oblivious to the facts emerging about her own record on equal pay and promoting women to positions of authority,” said Harmeet Dhillon, of San Francisco, vice chairwoman of the California Republican Party.

Conservative media recently reported Clinton as a senator paid her female staffers 72 cents on the dollar compared with men. And Dhillon said Clinton’s campaign is replete with “male Obama retreads rather than blazing a path for women in politics by offering them leadership opportunities.”

As usual, the former first lady, U.S. senator and secretary of state danced around the question of her presidential ambitions.

Working for change and women’s progress “doesn’t have to be dramatic — you don’t have to run for office,” Clinton said, pausing for a coy smile and thunderous applause, “although if you do, more power to you.”

Questioned after her 35-minute speech by noted Silicon Valley pundit Kara Swisher, Clinton said she’s still thinking a candidacy through. But “with so many big issues we have to deal with, unless we can come together and have a national conversation about these things, we’re not going to make the progress we need,” she said. “That would be my objective if I decide to do this.”

Whoever runs, “we have to restore economic growth with rising wages … and we have to restore trust and cooperation in our political system so we can act like the great country we are,” Clinton said. “We have to figure out how we can have a foundation in our economy again that makes people feel that their hard work and productivity will be rewarded.”

Asked why the nation needs a woman as president, Clinton replied that “the experience of being a woman, the ability to see what others might not see as gender discrimination or marginalization, gives us the ability to speak up and make changes.

“Women in public life do bring that perspective that we need.”

Josh Richman covers politics. Follow him at Twitter.com/Josh_Richman. Read the Political Blotter at IBAbuzz.com/politics.