Ronald A. Klain served as a senior White House aide to Presidents Barack Obama and Bill Clinton and was a senior adviser to Hillary Clinton’s 2016 campaign.

The only three things certain in life are death, taxes . . . and Democrats losing the debate on taxes. But 2017 could be the year when Republicans are on the defensive on tax reform.

President Trump and congressional Republicans plan to follow their health-care debacle with a massive tax-reform package. It’s far from clear how they will pay for it: Trump has previously promised that his tax changes would not “add to our debt and deficit ” and was counting on $800 billion taken from Obamacare to pay for tax reductions; perhaps this is why he recently said he’s going to try to return to, and finish, repealing the Affordable Care Act before taking on tax reform. It’s also not clear why tax reform is so high on the agenda, when voters are more eager for the president to deliver on his promised infrastructure package than to reduce the corporate tax rate. But the donor class must be heeded, and nothing heals Republican rifts like a good tax cut — so tax reform is on deck.

What exactly will be in Trump’s tax plan is a mystery. During the campaign, Trump promised three headline ideas: tax cuts for individual taxpayers, which would largely benefit the wealthiest; tax cuts for corporations, to reduce rates to 15 percent; and a series of tax cuts and changes to discourage job losses overseas. So how should Democrats respond?

First, they should put less emphasis on their usual critique — that GOP tax plans favor the rich — and focus relentlessly on one theme: jobs. Yes, the Trump plan will offer massive largesse to those who need it the least, and that is an outrage. But this well-worn argument is unlikely to break through today’s media clamor. Better to put the Trump plan to a test of Trump’s own creation: Will it help create jobs?

(Jenny Starrs/The Washington Post)

If lowering corporate rates is supposed to create jobs, Democrats should hold Trump to that promise, requiring that at least half of any corporate tax savings be invested in increased hiring and pay. If companies don’t do that, they should have to pay the higher tax rate now in place. Likewise, Trump has said that lower corporate rates will result in jobs returning to the United States. Surely, then, he would be willing to make corporations forfeit any tax relief if they add more jobs abroad than at home?

Trump has said that corporations will create jobs by bringing home cash that has been stashed tax-free overseas; again, why not insist that companies document that the returned cash is going to add jobs and raise pay — or else pay taxes on it? Another option is Rep. John Delaney’s (D-Md.) bipartisan plan to tax a part of any cash coming home to fund job-creating infrastructure projects. If Republicans won’t agree that flimsy promises about job creation be matched with binding requirements and stinging penalties, Democrats must make the point that, whatever the GOP tax reform might be, a jobs plan it isn’t.

Second, although the job of the opposition party is generally to oppose, tax reform is one area where the opposition cannot beat something with nothing. Democrats need to have an alternative proposal to put up against the GOP plan.

A wonkish plan that gets rave reviews from think tanks but gains no traction among taxpayers — or voters — won’t do the trick. Save it for the first transition team meeting in November 2020. For now, Democrats need a straightforward, middle-class tax-cut plan, like those Maggie Hassan and Catherine Cortez Masto proposed during last year’s campaign: a tax cut of $1,000 per family, paid for by closing loopholes that benefit the wealthy and big corporations.

Some Democrats resist such broad middle-class tax cuts, worried about the impact on government revenue. They think they feel like giveaways. But Democrats cannot stand for the notion that middle-class families are pinched and they feel their pain if they aren’t prepared to come forward with a concrete way to address that. An extra $1,000 in each family’s pocket is specific and on target.

Finally, if Republicans need Democratic votes to get a plan passed, Democrats should unify behind one simple demand: requiring the president to release all of his tax returns before the first corporate tax cut takes effect. The recently disclosed Trump tax return for 2005 revealed that virtually all of the taxes he paid resulted from the alternative minimum tax — a provision that his tax plan would eliminate. If that return is typical, the Trump tax plan is an 86 percent tax cut for . . . Trump. Voters have a right to know exactly what he is getting out of all of this, and Democrats should insist on the release of Trump’s tax returns as a condition of any tax-reform package.