If the tax plan of the Republican presidential candidate Donald Trump is overly ambitious, that of his Democratic Party rival Hillary Clinton is too modest to have a major economic impact. “It’s night and day,” says Roberton C. Williams , fellow at the Urban Institute-Brookings Tax Policy Center of the differences. Trump is promising massive tax cuts for individuals and businesses, but his plan will cause a .2 trillion revenue loss over 10 years, according to a study by the Tax Policy Center . However, seven million families will pay higher taxes with changes in exemptions and the standard deduction. Clinton’s plan would raise taxes on the wealthiest one percent, but grow tax revenues by only .5 trillion over 10 years. She also wants to expand child tax credits for low-income families. Trump’s tax cuts would worsen the national debt, which is set to cross $20 trillion (it’s at $18.96 trillion now), says James R. Hines, Jr. , law professor at the University of Michigan.…