Gay-rights advocates accused Bush of trying to exploit unease over homosexuality for political gain, at the risk of encouraging animosity toward gays and lesbians. Social conservatives, a key element of the Republican base, hailed his decision as a victory for traditional families.
Top Republicans in Congress signaled that they were in no hurry to take up the proposed amendment, even though Bush urged swift action. And changing the Constitution is a protracted process that has succeeded only a limited number of times.
Bush, who initially resisted altering the Constitution as the issue gained prominence over the last year, said recent court rulings and the growing number of gay marriages left him no choice.
"After more than two centuries of American jurisprudence, and millennia of human experience, a few judges and local authorities are presuming to change the most fundamental institution of civilization," he said. "If we are to prevent the meaning of marriage from being changed forever, our nation must enact a constitutional amendment to protect marriage in America."
He left open the possibility that states could approve civil unions and other forms of domestic partnership that carry some of the same legal rights as marriage, but other states would not have to recognize them.
An amendment, he said, should "fully protect marriage, while leaving state legislatures free to make their own choices in defining legal arrangements other than marriage."
Sens. John Kerry and John Edwards, the leading candidates for the Democratic presidential nomination, accused Bush of trying to divert attention from more pressing problems. Both said they personally opposed gay marriage but thought the issue should be left to the states.
