Donald J. Trump’s proposal to cut taxes — notably for the wealthiest Americans — is getting considerable play in conservative media and political circles.

The president thinks he’s on to something. He has pitched what his team has called the most sweeping “tax reform” package in U.S. history.

Now …

Let’s get real for a moment.

* The president also wants to enact a few big projects. He has proposed spending an additional $54 billion next year alone on the Department of Defense. He contends the military is depleted and, of course, blames the previous administration for all but rendering us defenseless against our enemies.

* He also wants to rebuild our nation’s roads, bridges and airports. The price tag for that? A cool $1.2 trillion. This is a project worth doing, given the sorry state of our highways and airports. I’m still baffled as to how this plays among fiscal conservatives who (a) voted for Trump in 2016 and (b) say they dislike spending money the government doesn’t have in the bank.

* The president also wants to build that “big, beautiful wall” along our southern border. The price tag varies on this matter, but I’ll go with the bigger number that’s been floated: $25 billion. I do not believe the wall will be built. Nor should it be built. Still, the president insists that it will and he no longer is saying at every campaign-style rally that “Mexico will pay for it.”

These things do not pay for themselves. Thus, Americans across the land need to ask themselves: Are we willing to step up to shoulder the cost of all these projects or are we going to ignore the reality that the money must come from each of us?

The tax cut mantra has become standard Republican Party policy. President Reagan famously sought to cut taxes while “rebuilding” the military. He railed against President Carter’s budget deficits, only to preside over a skyrocketing deficit during his two terms in office. President George H.W. Bush challenged us to “read my lips” while vowing at the GOP convention in 1988 to never raise taxes; which helped get him elected. He then raised taxes — wisely, in my view — and it cost him votes among his conservative GOP base in 1992. President George W. Bush cut taxes in 2001, then went to war with international terrorists after the 9/11 attacks; the deficits exploded.

A new Republican president is now proposing another massive tax cut while at the same time seeking to do big things. With what, Mr. President? Where’s the money coming from?

I hate the wall idea. If the president wants to stem illegal immigration, then invest more money in better enforcement along both of our lengthy borders — north and south — and at ports of entry along all three coasts.

The defense buildup doesn’t need to cost nearly what Trump is proposing. Our military remains the strongest in the world.

Infrastructure improvement makes sense, but it’s going to cost Americans a lot of money to get it done.

Are we going to fall for the GOP tax-cut dodge because we don’t want to pay for the things we insist that government do for us? Or are we going to understand that our government requires us to spend a bit of our money to make it work?