At a hearing of the House Judiciary Committee, Deval Patrick, Assistant Attorney-General for Civil Rights, said federal agencies had found no evidence of a conspiracy behind the burnings - 60 such incidents across 10 states in the past six years, according to the count of one civil-liberties group.
But, Mr Patrick said, the department was investigating whether "any individual or specific group" was organising "this epidemic of terror".
Unarguably, however, the problem is growing rapidly worse, with 22 cases in the past six months, after a mere three or four a year on average at the start of the decade. Most have occurred in small towns.
The government's Bureau of Alcohol, Tobacco and Firearms (ATF) is investigating 25 burnings since the start of last year, in several of which arrests have been made and convictions secured, all of white males, some with links to the Ku Klux Klan. A group calling itself "Skinheads for White Justice" is, for instance, linked to a burning in Knoxville, Tennessee on 8 January this year.
Thus are the ghosts of racial oppression and civil-rights struggles past once again stalking the states of the old Confederacy, just as the region seeks to use this summer's Olympic Games in Atlanta to project itself to the world as a modern, emancipated and economically vibrant "New South".
The arson cases were "a haunting echo from our region's troubled past", the Atlanta Constitution newspaper wrote last month, before noting differences between now and 30 years ago, when churches, then as now the very glue of Southern black culture, were a prime target of the Klan and other groups fighting to maintain white supremacy.
"At the height of the resistance against civil-rights reforms, such domestic terrorism was publicly criticised but was in fact accepted or condoned by a large portion of the white populace." Today, said the paper, those responsible were "extremist hate-mongers, whose philosophy would be rejected by nearly everyone ... their brutality speaks for no one but themselves."
And the apparent absence of a concerted campaign tends to support that view.
For much of black America, however, burnings are all too easily explained as a natural consequence to the thinly veiled racism that has crept anew into national politics - shaped by theorisers on the conservative right, visible in the backlash against affirmative action, and fanned by the rhetoric of politicians like the commentator Pat Buchanan during the recent presidential primaries.
The civil-rights leader Jesse Jackson recently warned of how "the clouds are seeded with scapegoat politics" after visiting the ruins of one burned church in South Carolina, a reference to the growing readiness of the right to blame the black populace for most of the crime, violence and other ills that plague American society.
But the Clinton administration too has come under fire for dragging its heels on the church burnings.
Nor has it gone unnoticed that, while rushing to hold hearings on Waco and Ruby Ridge, two tragedies involving white isolationists and cult leaders who fell foul of the ATF and the FBI, the Republican Congress has waited for years before investigating terrorism against blacks.
"There is a disparity in the way justice is dispensed in this country," Representative John Conyers, leader of the Congressional Black Caucus, said yesterday.
The church burnings, one of them in Richmond, Virginia, barely 100 miles south Washington, are by no means the only evidence of sharpened racial tension in the South.
In a case which shocked the country in December, three white soldiers from the 82nd Airborne Division in Fort Bragg, North Carolina, have been accused of the wanton racial murder of a black couple as they walked down a street in the nearby town of Fayetteville. Nazi and white-supremacist literature were found in the quarters of one of those charged.Reuse content