Such things as a militay to protect us, a Federal Government to assist in leading us, different departments to help protect us from ourselve and other, and a national road system that all can use for their benefit.
The original tax code system basically stated that you, as a tax paying citizen, can either send your money to us, the Federal Government, and we will determine where and how it can be use best for the general benefit of all citizens; OR you can keep all or part of your taxes IF you invest your money back into the US by such methods as creating a family including children, business investment, real estate investment and a few other methods. All these exceptions to the tax code beneift everyone from the local community to the greater good of the US.
Most of those exceptions still apply. Ask anyone who has a family (deductions), owns a business (deductions), owns their own home (deductions), invests in charaties (deductions) or even adopts childred from around the world so they can have a decent chance of having a decent life (deductions).