Critics of the plan have mostly ignored that substantial elements of it have drawn bipartisan support. Almost everyone agrees that corporate tax rates need to be cut because of global competition. Companies should not be able to stash earnings overseas tax-free. With the standard deduction doubled, many more individual taxpayers could file a simple short-form return. A lower rate for small businesses and pass-through entities, while more controversial, should promote economic growth.

“The most important things for the middle class will be better economic performance and growth in wages,” said Douglas Holtz-Eakin, president of the American Action Forum, a conservative pro-growth advocacy group. “That’s a much more powerful force than any tax policy. From that perspective, this is a promising start. But it’s only a start.”

Representative Kevin Brady, Republican of Texas and the chairman of the House Ways and Means Committee, told me this week that he was determined to get a tax bill to the president by the end of the year.

“Is that ambitious?” asked Mr. Brady. “Absolutely. President Reagan’s reform took two and a half years. We’re trying to do it in one year.” But the economy and the public are desperately in need of tax reform, he added, and “we are continuing to work on the final design of the tax reform plan that we’ll have ready after the budget is complete.”

The biggest challenge for legislators is that corporate tax cuts are costly. The Tax Policy Center, in a preliminary analysis, calculated that reducing the corporate rate to 20 percent and eliminating the corporate alternative minimum tax would cost the Treasury nearly $2 trillion over the decade from 2018 to 2027.