IT IS AN OPEN secret in the national movement supporting school “choice” — South Carolina is considered a test case, fertile territory for a statewide experiment to move public money to private schools:

Our governor is all for a significant shift of public resources to private schools in the form of tax credits. Our conservative populace is considered sympathetic to such libertarian notions. Our geographically small state is viewed as easy pickings for interest groups with big bucks. Saturating our media markets with commercials is far less expensive here than elsewhere.

You’ve heard of “South Carolinians for Responsible Government,” the movement’s S.C. face. You don’t hear from tax credit advocates about the big picture.

A spokesman for the National Association of School Boards told The Charlotte Observer that South Carolina is the top battleground in the country for the “choice” lobby, based on the time and money it has spent here. Sam Daniels, consultant for the Michigan-based choice group “All Children Matter,” told the paper a win in South Carolina will provide momentum. (Outsiders have spent at least $400,000 here trying to elect candidates and influence the Legislature. Before the election, All Children Matter had raised at least $919,500 to spend in South Carolina and other states.)

What is most troubling is that these national groups have no stake in whether their experiment leaves South Carolina better off, or worse.

They are fueled by ideology. They have deep philosophical objections to what they call “government” schools (because government, to them, is inherently bad). The voucher fight is but one aspect of their efforts to defund the basic structures of American democracy.

These groups’ resources are nothing to be scoffed at. They tap into the reserves of wealthy individuals and foundations that exist to promote their view. The national voucher movement draws support from individuals connected with such names as Wal-Mart, Amway and Coors. They share deep pockets and deep ideological objections to so-called “big government.” They have one other thing in common — an utter lack of knowledge about or real interest in the ultimate success or failure of South Carolina’s children.

They don’t care that tax credits would derail one of the nation’s most robust public school improvement efforts, which is having such remarkable positive effects in our state. They would brush aside the reforms pushed by our business leaders, by our responsible community leaders, elected officials, teachers and parents.

South Carolina’s schools are not where they need to be yet, not by a long shot. But the way to move them farther from that critical goal is to allow reform to be hijacked by outside political interests. We must let these political carpetbaggers know that South Carolina is more than a notch on someone’s belt. We are a real state with real children whose future is nothing to gamble with.

To read the rest of this series so far, go to http://www.thestate.com/, click on “Opinion,” and then on “Our Children, Our Schools.”