The massive expansions of just about all of the programs the Trump plan seeks to cut have led to a growing number of unemployed people in America who are just getting by on various forms and levels of government assistance. This puts an undue level of new strain on the people who actually are working and paying payroll and other taxes to prop up the rest of the country. Yes, Mitt Romney was roundly pilloried when he complained that 47 percent of the people would never vote for him because they pay no federal taxes. But what part of what Romney said was factually wrong? What part of what he said wasn't indicative of an unsustainable political and economic reality? The Trump budget at least starts to tell us the truth about what benefits can survive even in the short-term future.

And there's another harsh but crucial reality in the Trump budget — it knows where the money comes from. Taxpayers. Somehow, prioritizing the people who actually provide us the money to spend in Washington has been portrayed as selfish or mean.

Now, let's get to what the Trump budget gets wrong. In short, it still isn't "harsh" enough. So far, we have no details of any reforms to the three biggest problems in our budget: Medicare, Social Security, and Defense. No real anti-deficit and pro-taxpayer moves can be made permanent until all three of those programs are reformed and essentially cut. It's not surprising the White House plan doesn't make the hard choices on that three-headed fiscal monster considering it would make the current political firestorm over his other cuts look like a small campfire.

The political class and the news media remains convinced that the public will never accept even the slightest cuts or even any significant changes to those programs, but that's just plain wrong. 41 percent of Americans don't believe that Social Security will even exist when they retire, according to a survey by the Pew Research Center. Are we supposed to believe that they won't stand for changes to a program they don't expect to be around for much longer? Politicians simply don't want to bother to make those tough choices and they're hiding behind the voters to avoid them.

But first things first. You have to start telling the truth somewhere, and the Trump budget does the most truth telling since at least the cut-heavy Reagan budget in 1981 that helped launch a major economic expansion. Our debt is about $20 trillion, and the number of unfunded liabilities coming due in the future have some experts pegging our real debt at more like $200 trillion. There's not enough taxpayer money in the universe to cover those costs.

With these harsh truths in mind, we have to remember that a budget that doesn't make the harsh cuts Trump's does simply isn't realistic. Oh, and there's no such thing as unicorns either.

Commentary by Jake Novak, CNBC.com senior columnist. Follow him on Twitter @jakejakeny.

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