Story highlights Hillary Clinton: We need to continue to fight discrimination at all levels of government

We must ensure America remains on the right side of history, she says

Former U.S. Secretary of State Hillary Clinton is a candidate for the Democratic nomination for president. The opinions expressed in this commentary are hers.

(CNN) As we enter Pride Month, and reflect on what has transpired in the last year, it's clear that America took some big steps forward in our ongoing fight for equality.

Marriage equality is the law of the land. The federal government and U.S. military's nondiscrimination policies now cover sexual orientation. Adoption by same-sex couples is finally legal in every state.

Hillary Clinton

And in communities across the country, high schools are celebrating same-sex prom kings and queens. Transgender people have been living with greater openness and joy. There's no denying that our country is moving forward.

Now we need to make sure America remains on the right side of history. We're already seeing efforts to reverse the gains we've made in statehouses and courthouses across the country. Not to mention, there's an election going on -- and it would be all too easy for our next president to roll back much of the progress we have made.

Enter Donald Trump, who has pledged to do just that.