In a moving tribute to his son Will, who is gay, Ohio Sen. Rob Portman announced his support of marriage equality. The celebrated conservative senator, once on the short list to become Mitt Romney’s running mate in 2012, writes in a column published today in The Columbus Dispatch:

I have come to believe that if two people are prepared to make a lifetime commitment to love and care for each other in good times and in bad, the government shouldn’t deny them the opportunity to get married.

That isn’t how I’ve always felt. As a congressman, and more recently as a senator, I opposed marriage for same-sex couples. Then something happened that led me to think through my ...