(CNN) -- Sometimes the hardest thing is to say "no" to a friend. All the more reason to applaud the bravery of Lee Saunders and the American Federation of State, County and Municipal Employees.
A few months ago, the United Negro College Fund accepted a $25 million grant from Charles and David Koch to support scholarships for minority students. It raised more than a few eyebrows. After all, everyone -- including me -- reveres the college fund. Its contribution to the cause of equal opportunity is legendary.
The Koch brothers are one of the most prominent funders of organizations that work to restrict early voting and registration and effectively disenfranchise African-Americans. They oppose the minimum wage, which would disproportionately help black workers. They are spending millions to lie to the public about climate disruption, which hurts the most vulnerable communities first.
In other words, the Koch brothers' agenda is great for African-Americans -- so long as we do not want to vote, make a living or avoid our homes being swept away in a flood.
It is one thing to accept money from dubious sources. One could argue -- convincingly -- that the college fund was taking money from a bad source and doing something good with it.
But the breaking point came a few weeks ago when United Negro College Fund President Michael Lomax appeared at a Koch brothers' retreat in California. The public stated purpose of this event was to build support for the Koch brothers' various political causes. The moment he stepped through the door, Lomax lent the his organization's good name to a radical agenda that causes untold damage to African-Americans.
All this was too much for AFSCME, a predominantly African-American union with a long civil rights track record that had partnered with the United Negro College Fund for years in giving out scholarships. Last month, Saunders sent Lomax a letter ending their partnership.
It was a tough decision, no doubt -- but it was the right one. (Full disclosure: AFSCME once made a donation to Rebuild the Dream, an organization that I lead.)
I am all for education. That is one of the reasons I helped start #YesWeCode, an initiative to teach computer science to black, brown and low-income young people. I am the first to point out how much brilliance and creativity our nation is losing by failing to uplift youth from low-opportunity backgrounds. That's why I am usually such a huge fan of the United Negro College Fund.