The president can only propose a budget. He cannot force the Congress to accept it. The Constitution, which is the supreme law of the land, gives sole responsibility to the House of Representatives for originating appropriations and taxes.
O'neill is the speaker of the House. He is the leader of the majority party. He and his fellow Democrats, not the president, can approve any budget they want. If the president vetos it, they can pass it over his veto.
I can't think of a single domestic problem, from an unfair tax code to defense overruns, that is not traceable directly to those 545 people.
When you fully grasp the plain truth that 545 people exercise power of the federal government, then it must follow that what exists is what they want to exist.
If the tax code is unfair, it's because they want it unfair. If the budget is in the red, it's because they want it in the red. If the Marines are in Lebanon, it's because they want them in Lebanon.
There are no insoluble government problems. Do not let these 545 people shift the blame to bureaucrats, whom they hire and whose jobs they can abolish; to lobbyists, whose gifts and advice they can reject; to regulators, to whom they give the power to regulate and from whom they can take it.
Above all, do not let them con you into the belief that there exist disembodied mystical forces like "the economy," "inflation" or "politics" that prevent them from doing what they take an oath to do.
Those 545 people and they alone are responsible. They and they alone have the power. They and they alone should be held accountable by the people who are their bosses - provided they have the gumption to manage their own employees.