House Republicans will "lead with our chin" and offer politically explosive cost curbs this spring on programs like Medicare, Medicaid and perhaps Social Security, the party's point man for curbing crippling budget deficits said Thursday. Even then, Rep. Paul Ryan acknowledged, the government's budget still won't balance for quite some time. In a wide-ranging interview with The Associated Press, the Wisconsin lawmaker and chairman of the House Budget Committee said the House Republicans' budget proposal for the 2012 fiscal year that begins Oct. 1 will propose fundamental changes to Medicare and Medicaid, the giant healthcare programs that cover 100 million Americans and whose combined costs rival the defense budget. Ryan offered no specifics, saying details are still being hashed out.