Florida's Supreme Court last week was the latest venue for the movable feast of meretricious arguments by which public-school teachers unions wage war in any city or state where families of poor children try to escape from failing public schools. The attack on Florida's school-choice program relied on 19th-century bigotry and 21st-century obscurantism.

Florida's Opportunity Scholarships, the nation's first statewide school-choice program, was enacted in 1999 to ameliorate a gross civil-rights injustice--the fact that poor families whose children are trapped in terrible schools are helpless to prevent their children's life chances from being blighted. The program empowers students to transfer from failing schools, as defined by set criteria, to the public or private school of their choice.

Teachers unions immediately filed suit to block this escape route--this underground railroad, if you will--from the public-school plantation. The suit cited two provisions of Florida's constitution.

One is its Blaine amendment, which says no public money shall go "directly or indirectly in aid of any church, sect, or religious denomination or in aid of any sectarian institution." The other says the state must make "adequate provision" for "a uniform, efficient, safe, secure, and high quality system of free public schools."

Blaine amendments are named after Maine Sen. James G. Blaine, who sought the Republicans' 1876 presidential nomination, when fear and loathing of Catholic immigrants was pervasive. As early as 1855, Massachusetts's governor, every member of the state Senate and all but four members of the state House were members of the anti-Catholic Know-Nothing Party, and the legislature established a Nunnery Investigating Committee to search for underground dungeons in convents.

Many states such as Florida adopted Blaine amendments to their constitutions--and Congress required them in the constitutions of new states joining the union. That these amendments were anti-Catholic is indisputable: they proliferated at a time when Protestantism was the established religion in America's public schools. Education reformer Horace Mann said the public school should be a "nursery of piety" dispensing "judicious religious instruction." Judicious meant using the King James Version of the Bible and combating "the superstitious inheritance of priestcraft."

Opponents of Opportunity Scholarships say they violate Florida's Blaine amendment by being usable at religious schools. But this argument has three flaws.

First, the scholarships are not "in aid of" any religious institution. Rather, they are intended to promote the general public welfare by improving, through accountability and competition, Florida's public schools. Although the program permits the use of scholarships at religious schools, it neither favors nor encourages such use, and any benefit such schools receive is merely incidental to the purpose of improving public schools.

Second, the U.S. Supreme Court has held that school-choice programs similar to Florida's "have a valid secular purpose" and involve "true private choice" because government scholarship aid goes directly to parents, who use it at their discretion. It "reaches religious schools only as a result of the genuine and independent choices of private individuals," so any "incidental" benefit to religious institutions involves "no imprimatur of state approval."

Third, although the sort of people who fight against poor children are not very susceptible to shame, even they may be ashamed to rely on the Blaine amendment, that residue of 19th-century bigotry. Hence their reliance on the "uniformity" clause. But that reliance has two problems.

First, a "uniform" public-school system cannot mean that all schools must be identical. Neither does it mean that the state legislature must concern itself exclusively with providing access to public schools. Rather, the term "uniform" means merely that no child shall be denied access to the public system. As long as the legislature fulfills that constitutional duty, it can additionally promote the general welfare by using ingredients of private education. Indeed, the teachers unions say that the state, consistent with its duty to provide "uniform" education, can send children with special needs to private schools.

Second, the Institute for Justice, the merry band of libertarian litigators who are defending Floridians desperate for school choice, says: There is nothing "uniform" about a state school system in which many schools--mostly attended by minority children from poor families--are consistently assigned an F grade by the state, while many other schools, particularly in affluent areas, consistently receive high state grades for delivering the "high quality" education to which Florida's constitution says all the state's children are entitled.

Why do the teachers unions fighting poor families focus only on the word "uniform"? What about the other adjectives in Florida's constitution? Does anyone think Florida is providing all students with public schools that are "efficient, safe, secure, and high quality"? Can the unions assert that without blushing? Probably.