American Jews who were listening this week heard a crash ricocheting across the land.

It was the sound of building blocks tumbling down from the wall separating church and state.

The Supreme Court issued two key rulings that Jewish activists are saying could deal a deadly blow to the First Amendment's shield against government interference in religious practice.

First, the high court Monday ruled 5-4 Monday, in Agostini vs. Felton, that public schools can send teachers into private parochial schools for remedial instruction.

Two days later, in Boerne vs. Flores, the court ruled 6-3 that Congress overstepped its constitutional bounds with the 1993 Religious Freedom Restoration Act that required the federal, state and local governments to show "compelling" reasons before imposing a "substantial burden" on personal religious beliefs.

Church-state separationists warn that the first decision could open the door to a range of attempts at government support of religious institutions, including vouchers for private schools.

The second ruling, they say, could leave Jews vulnerable on the local and state level to laws restricting their religious practice, which could include the ban on wearing hats inside public buildings.

As Charles Haynes of the Nashville, Tenn.-based First Amendment Center said of Agostini vs. Felton, "The decision will raise questions in some minds about how high a wall of separation there should be under the First Amendment's Establishment clause."

Haynes was referring, of course, to the Constitution's ban on government establishing any religious institution.

Jewish activists are no less worried, and they are warning that the court rulings are opening the floodgates to attempts to further erode the wall between church and state.

It remains to be seen just how far the wall separating church and state will fall. But that barrier has toppled, and Jews across America will be feeling a dangerous wind blowing through.