Back in 1992, vacationing on the Big Island of Hawaii, I walked toward a river of blood-red lava shooting over a cliff and into the sea.

Some things in life you don't forget. Lava is like that. I recall looking for a sign, rope or "Hawaii Five-O's" Steve McGarrett to warn me to stop.

But a giant caution sign wasn't necessary. I recall the instant I knew not to step a hair's breadth further: I could feel the soles of my tennis shoes starting to soften.

A similarly invisible, red-hot warning — "Tread closer at your own peril" — poured out from the U.S. Supreme Court this term to gay Americans.

The Roberts Court — whose votes in a series of non-gay cases strongly signaled that Chief Justice John Roberts and Justice Samuel Alito can be expected to join Justices Antonin Scalia and Clarence Thomas in opposing most any imaginable gay-rights plea — is moving frighteningly close to having the five votes it would need to weaken the groundbreaking rulings of 1996 and 2003 acknowledging that gay Americans are protected by the Constitution.

Gone is tenuous supporter Sandra Day O'Connor, who before retiring sided with gay Americans in Romer v. Evans in 1996 and Lawrence v. Texas in 2003 — both 6-to-3 decisions.

Only five gay-rights allies remain: Anthony Kennedy, who penned the pair of legal aces; John Paul Stevens, now 87; David Souter; Stephen Breyer; and Ruth Bader Ginsburg. And no one can be certain just how far any of the five — especially Kennedy, who has become the court's conservative swing vote — would go to protect gay Americans in cases less outrageously extreme. In Romer, Colorado had tried fence its gay citizens out of the normal political process. In Lawrence, a gay Texas couple was arrested for having sex at the home of one of the men.

"Many of us were worried about what it would mean to have Justice Roberts become chief justice and Justice Alito to replace Justice O'Connor. This term confirmed a lot of our fears," says Jon Davidson, legal director at Lambda Legal Defense and Education Fund.

What alarmed gay rights litigators? A string of 5-to-4 decisions against the powerless or minorities — rulings blocking workers from suing over sex discrimination if it's not discovered immediately, ignoring public school students' free-speech rights and hampering efforts to create racially diverse schools.

"The U.S. Supreme Court was for a long time a protector of minority groups, and it has become less so over time," notes James Esseks, a gay litigator at the American Civil Liberties Union. "I'm worried that a future Supreme Court would narrowly interpret or even cut back Romer and Lawrence."

Sensing the Court's rising temperature, most gay-rights litigators are wisely avoiding the federal judiciary system altogether. But cases already in lower federal courts could severely burn the gay rights movement. They involve an Air Force flight nurse featured on recruitment posters, then booted out for being gay; lesbian couples asking Uncle Sam to recognize their Canadian marriages; a Texas woman who lost a job offer because she is transgender; and gay-friendly schools attempting to feel welcoming.

The protections won in Romer and Lawrence are fragile, unlikely to be built upon soon. A smoking volcano looms above them. This Supreme Court could erupt.

Deb Price of The Detroit News writes the first nationally syndicated column on gay issues. To find out more about Deb Price and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate web page at www.creators.com.