Like Social Security, unemployment compensation, and health insurance such as Medicare and Medicaid - all gains that the working class has won over decades - public education is a way that working people collectively get back a small portion of the value they produce from the capitalist class as a whole. These programs provide some possibility for workers to make it through a lifetime: to have pensions, to be able to provide care for the young, to get some education.
For more than a decade, these social gains have been under attack by the employers and both parties that represent them, Democrats and Republicans, alongside the bosses' direct offensive to drive down wages and working conditions. Their aim is to put more of the burden for social responsibilities on individual workers and their families. That's where the initial steps to undercut public education, in the form of vouchers or "charter schools," comes from.
Education doesn't rise above the class basis of society. Under the capitalist system the public schools serve primarily to train working-class youth for a life of subservience to a boss, while breaking down human solidarity. Millions of young people do not gain even basic literacy from these institutions, and the conditions are worsening in face of today's growing economic crisis.
Some people, including some workers, respond by seeking individual solutions they hope can improve education for their children, including schemes like charter schools and vouchers.
Ultrarightists such as Patrick Buchanan seize on this as part of their "culture war." In calling for general education "vouchers" - in other words, an end to universal public education - Buchanan harps on about moral decay, secularism, and drug-dealing "hoodlum kids." He attempts to whip up an emotional reaction against an ever-widening layer of scapegoats who he claims are responsible for the economic and social devastation caused by the capitalist system. The rightist movement he seeks to build will ultimately be used against the organizations of the working class.
The right to a free, public, and secular education is a democratic gain for the working class that has been won and extended in struggle. The first free public schools in the South of the United States, for instance, were established in the period of Radical Reconstruction following the Civil War, as former slaves fought to win full equality and rights.
Defending public education is part of fighting for the social solidarity of the working class - solidarity that is needed to build a movement that can fight to overturn the capitalist system and forge a workers and farmers government. That is the only way to finally achieve real education as a lifetime right for all.