In bits and pieces, the signs are everywhere that the conservative Christian religious movement is directing the policies of the Republican Party. But it took a conservative Republican politician – who is also an ordained Episcopal minister – to put them all together and say so.

John C. Danforth, a three-term Republican senator from Missouri and briefly U.S. ambassador to the United Nations under President George W. Bush, issued a warning to his party in a recent op-ed column in The New York Times. He wrote: “By a series of recent initiatives, Republicans have transformed our party into the political arm of conservative Christians.”

As elements of this transformation, he listed advocacy of a constitutional amendment to ban gay marriage, opposition to stem cell research “involving both human embryos and human cells in petri dishes” and “the extraordinary effort to keep Terri Schiavo hooked up to a feeding tube.” He described those elements as “parts of a larger package, an agenda of positions common to conservative Christians and the dominant wing of the Republican Party.”

In an interview with the St. Louis Post-Dispatch, which reprinted his article, Mr. Danforth said: “It becomes extraordinarily divisive, and legislatures get themselves entangled with writing religious documents into legislative form. It’s exactly what the Constitution says we can’t do, and it’s exactly what we can’t do if we want to keep the country glued together.” He added: “I’m surprised people have been so mute about this. I thought if nobody was saying this, I should.”

On the Schiavo case, his column said: “High-profile Republican efforts to prolong the life of Ms. Schiavo, including departures from Republican principles like approving Congressional involvement in private decisions and empowering a federal court to overrule a state court, can rightfully be interpreted as yielding to the pressure of religious power blocs.”

He also mentioned a current Missouri controversy in which the state’s General Assembly had advanced legislation to criminalize even stem cell research in which the cells are artificially produced in petri dishes and will never be transplanted into the human uterus. “It is not evident to many of us that cells in a petri dish are equivalent to identifiable people suffering from terrible diseases. I am and have always been pro-life. But the only explanation for legislators comparing cells in a petri dish to babies in the womb is the extension of religious doctrine into statutory law,” he wrote.

Mr. Danforth shares some of the positions of the religious right, including his long devotion to the anti-abortion movement and his support for Supreme Court Justice Clarence Thomas.

He wrote that during his 18 years in the Senate Republicans often disagreed with each other but were held together by basic principles including limited government shared by virtually all Republicans. “But in recent times, we Republicans have allowed this shared agenda to become secondary to the agenda of Christian conservatives. As a senator, I worried every day about the size of the federal deficit. I did not spend a single minute worrying about the effect of gays on the institution of marriage. Today, it seems to be the other way around.”

Mr. Danforth’s article was reminiscent of Maine’s Sen. Margaret Chase Smith’s 1950 “declaration of conscience” denouncing the anti-Communist demagoguery of Sen. Joseph McCarthy of Wisconsin. It could help generate resistance to a current drive by Christian conservative groups against the Senate’s filibuster rule, which they regard as vital to issues like abortion, prayer in the schools and same-sex marriage.