There are terrible ideas that wither over time, and there are some, like the payroll tax cut, that refuse to go away. Although payroll tax cuts would cut off the primary funding stream for Social Security — and serve as an inequitable and ineffective means to stimulate the economy — President Trump continues to peddle them anyway.

Social Security is exclusively funded by payroll contributions from workers and employers. Tampering with its funding is dangerous for the program, its 65 million beneficiaries and countless more Americans in years to come. In fact, we believe that additional cash relief payments that target lower and middle-income workers are a far better remedy for the financial pain so many are feeling.

President Trump has indicated he would like to see a permanent payroll tax cut, but even a temporary one could have dire consequences for Social Security.

The Social Security trustees recently reported that, unless Congress takes action to strengthen the program, its trust fund will become depleted in 15 years, after which it would only be able to pay 79% of benefits. That would leave the government with three choices: permanent benefit cuts, payroll tax increases or some combination of the two.

In order to avoid painful benefit cuts in the future, Social Security needs more revenue now — not less. I wrote a letter to President Trump explaining that any reductions to this vital revenue stream could threaten Social Security’s ability to continue paying benefits by reducing the trust funds from which benefits are paid. (The White House never responded to my letter.)

Even if Congress were to compensate for the loss of payroll tax contributions with general revenue, it still would undercut Social Security. One of the reasons this insurance program, which offers retirees and people with disabilities, along with their families, basic financial security, has endured for nearly 85 years is because it is worker-funded. That’s why we call it an earned benefit rather than an entitlement. Back filling Social Security with general revenue undermines that “earned benefit” principle, which so far has prevented so-called “entitlement reformers” from cutting or destroying the program.

Plus, substituting general revenue for payroll contributions also would strengthen the hand of fiscal hawks, who claim that Social Security is adding to the federal deficit, even though the program currently is self-funded.

Trump claims that a payroll tax cut serves as as an economic stimulus. But it would take months to realize any discernible impact. Any such effect would be limited because cutting payroll taxes would do nothing for the more than 40 million Americans who have filed for unemployment benefits since mid-March. And it would not put significant cash into the hands of the low-to-moderate income workers who are most likely to quickly spend it — which is the whole point of a stimulus policy.

Workers who are among the poorest 20% of earners would only receive about $200 annually from a 2% payroll tax break, as was enacted in 2011 and 2012, while the highest-earning employees would get up to $4,200 in relief. According to the Institute for Taxation and Economic Policy, nearly half of the benefits would go to the richest 20% of taxpayers, meaning they would not be particularly targeted to those who need help the most. That outcome is neither fair nor effective in a society already suffering from severe income inequality.

Small businesses that have already been forced to lay off employees also would see minimal relief from an employer payroll tax cut because their payrolls have significantly shrunk. Instead, employer payroll tax cuts would accrue mainly to the benefit of big businesses, which have the financial resources to keep employees on the payroll without federal relief.

Large majorities across party lines continue to support Social Security while opposing benefit cuts. They also recognize the financial lifeline that their earned benefits supply at a time of gross income inequality and diminished retirement savings — and now, during a global pandemic, 40% of seniors rely on Social Security for all of their retirement income. That’s how vital this program is.

The Trump administration has proposed billions of dollars in cuts to Social Security Disability Insurance and has enacted new rules that make it harder for Americans with disabilities to continue collecting benefits. Earlier this year, the president expressed an openness to cutting entitlements in a second term. But his obsession with obliterating payroll taxes, perhaps permanently, is the clearest indication of his malintent for Social Security.

Seniors must see this for what it is and unite in opposition to any politician who pays lip service to preserving Social Security while using the pandemic to upend it.