With the House's climactic vote on ObamaCare tomorrow, Democrats are on the cusp of a profound and historic mistake, comparable in our view to the Smoot-Hawley tariff and FDR's National Industrial Recovery Act. Everyone is preoccupied now with the politics, but ultimately at stake on Sunday is the kind of country America will be.

The consequences of this bill will not only be destructive for the health-care system and the country's fiscal condition, though those will be bad enough. Inextricably bound up in a plan as far-reaching and ambitious as ObamaCare are also larger questions about the role of government, the dynamism of American enterprise and the nature of a free society. Above anything else, this explains why Democrats have had such trouble convincing the public, let...