It's a testament to Americans' generosity that the wealthiest among her citizens are the ones who tend to give more of their incomes to charities such as soup kitchens, institutions of higher education or medical research. But that fact is also the center of a political controversy that too often pits advocates of bigger government against recipients of charitable generosity.

The Big Government advocates, led by President Obama, want to limit the tax deduction for charitable contributions because they believe it will increase the flow of money to the IRS. The Congressional Budget Office estimates that deduction was worth about $40 billion in 2013, with more than 80 percent going to the wealthiest 20 percent of taxpayers in terms of income, including 38 percent to the top 1 percent.

Currently, taxpayers who itemize can deduct charitable contributions up to 50 percent of their adjusted gross income, and the savings depends on their tax bracket — the higher the bracket, the more the savings. For the wealthiest taxpayers, that's 39.6 cents on every dollar contributed to charity.

Obama has proposed limiting the deduction to 28 percent of adjusted gross income for the wealthiest taxpayers, or 28 cents on every dollar contributed, hoping to redirect billions of dollars into federal coffers. But research has shown that such a proposal, if implemented, would cause charitable contributions to decline, and likely not increase revenue as that money is poured into one of numerous other tax shelters.

American Enterprise Institute President Arthur Brooks released research Dec. 3 that showed the proposal would decrease charitable contributions by $9.5 billion in the first year, with universities, symphony orchestras, some hospitals, and other nonprofits that rely disproportionately on wealthy donors hardest hit. And this comes at a time when charitable contributions are still struggling to recover from the Great Recession of 2008, he said.

This proposal, like much of Obama's latest efforts on the budget and economic fronts, shows how much the politics of resentment have triumphed over common sense in his second term. Instead of looking at what works, Obama continues to urge Americans to envy those who have become successful and covet what they have. And that proposal appears to be part of what the Senate Finance Committee is considering as it crafts an overhaul of the tax code that's expected to emerge next year.

The good news is opponents of Obama's approach received a recent boost from a bipartisan effort led by Finance Committee members Sens. John Thune, R-S.D., and Ron Wyden, D-Oregon. Thune and Wyden circulated a letter among their colleagues urging them to oppose any limits on the deduction: "The charitable deduction is unique. It is the only provision that encourages taxpayers to give away a portion of their income for the benefit of others. For this reason, it is not a loophole, but a lifeline for millions of Americans in need."

All told, more than $315 billion in charitable contributions were made last year, but, as National Review Online’s Kevin Williamson recently pointed out, “in fact tax deductions amount to about 12 percent of total charitable donations, meaning that our wily robber barons have figured out a way of beating the taxman by ... giving away far more money than they receive in related tax benefits.”