FREEPORT — Recent polls tell us that national security issues are uppermost in voters’ minds at the moment, so it’s no surprise that we know more about the Republican presidential candidates’ views on how to deal with the Islamic State or the Syrian refugee crisis than we know about their views on issues like taxes, spending or the deficit.

But these domestic issues will be around after the current foreign crises have at least diminished, and they will continue to have a powerful influence on the health of the economy.

Tax reform proposals are at the center of all of the Republican candidates’ economic plans. Being Republicans, they all want to reduce taxes and simplify the tax code.

Where there is enough detail to judge, the Tax Foundation estimates that the Republican plans would accomplish these goals and would also result in more jobs, stronger economic growth and increased capital investment compared to current policy or any proposal from Democratic candidates Hillary Clinton and Bernie Sanders.

But Republican tax proposals have one other thing in common: Even after allowing for positive economic effects, all of the plans would increase the deficit.

All of the current candidates propose measures designed to offset the revenue loss from tax cuts. These include the repatriation of overseas corporate cash at a low tax rate; the elimination of many tax credits and deductions, and the elimination of a variety of federal agencies. Some of these savings may be achievable, but others probably aren’t politically feasible.

None of this should be a surprise. Republicans invariably get priorities for tax and spending cuts backward. They always want to cut taxes first, and hope to offset the revenue loss with spending restraints that usually don’t happen. The result is some degree of economic stimulus, but also higher deficits.

Among the leading candidates, Ted Cruz’s plan produces the smallest revenue loss: $768 billion over 10 years after its positive economic effects. His plan consolidates seven existing personal income tax brackets into one at 10 percent; eliminates the payroll tax; eliminates all credits except for the child and earned income credits, and eliminates all deductions except for charitable contributions and mortgage interest.

The Texas senator would eliminate the corporate income tax and replace it with a value-added tax of 16 percent. The fly in the Cruz ointment is that a VAT can become a stealth tax because it can go up in small increments without too many people noticing.

Florida Sen. Marco Rubio proposes to reduce current tax brackets to two: 35 percent and 15 percent. His plan eliminates all deductions except for charitable contributions and mortgage interest. The plan would also replace the standard deduction with a refundable credit of $2,000, which means that some low-income individuals would not pay any taxes but would still get a refund.

Rubio’s proposal would also create a new $2,500 child credit. Tax credits are always arbitrary and discriminatory, and are responsible for a good deal of the complexity in the tax code, as well as significant lost revenue.

Rubio would do better to forgo new or increased credits and instead lower his bottom rate. Primarily because of the proposed new credits, the Tax Foundation estimates that Rubio’s plan would cost $2.4 trillion in lost revenue over 10 years.

Then there is Donald Trump’s plan, which is as bold and brassy as the candidate. It proposes three individual brackets of 10 percent, 20 percent and 25 percent. More importantly, it proposes to increase the standard deduction to $25,000 for single taxpayers and to $50,000 for joint filers. This means that over 50 percent of potential taxpayers would not pay any income tax.

The problem here is that individuals who don’t pay taxes have little incentive to care how much money the government spends, or on what. Not surprisingly, Trump’s plan would lower tax revenue by $10 trillion over 10 years.

Trump also wants to impose additional taxes on goods imported from China and Mexico, a misguided protectionist impulse that would be costly for American consumers. Will voters ever look past the populist rhetoric and focus on the consequences of his policies?

Most Republican candidates have the right ideas on tax simplification and lower rates. Their plans would be even better if spending were cut first and the savings used for tax relief. But this would make the process longer and harder, and it requires too much patience to be politically popular.