The Republican tax reform plan offered in Washington, D.C., may be many things. But at its most sinister it represents a direct attack on cities like Detroit that form the core of Democratic support.

That attack comes in the form of the proposed elimination of the federal historic tax credit. In use for several decades, the tax credit allows developers of historic properties to deduct up to 20% of their eligible expenses from their taxes.

Translated into everyday English, the credit reduces the cost of renovating older buildings in cities like Detroit. Without it, developers who hope to put empty, decaying structures to new use would have to borrow more money or convince more investors to bankroll their efforts.

So the historic tax credit makes it easier to pay for such rehab projects. That was the point of it all. Lawmakers nearly a half-century ago created the credit to help ailing legacy cities in the Northeast and Midwest resurrect themselves.

Creation of the tax credit reflected widespread dissatisfaction with the record of urban renewal, which in cities like Detroit relied on bulldozing entire neighborhoods, mostly occupied by poorer people of color. Critics like author Jane Jacobs in New York preached the value of creating a sense of place by renovating older historic neighborhoods rather than razing them.

Read more:

Trump tax plan would kill $7,500 credit for electric vehicle buyers

A simple tax cut isn't all that simple, depending on your financial situation

Michigan towns as small as Coldwater have put the credit to use in their historic districts. Between 2001 and 2016, the credit helped renovate 315 projects throughout Michigan, with a total investment of $1.84 billion, said Nancy Finegood, director of the Michigan Historic Preservation Network.

Thousands of jobs were created with the help of the credit, and thousands of new residential units built.

But clearly the biggest beneficiaries have been older legacy cities like Detroit, where it has proved essential. In Detroit, the federal tax credit has been part of the financing of virtually every rehab project in the city over the years.

“If it wasn’t for that credit, we wouldn’t see the revitalization we’ve seen downtown, Midtown, Capitol Park, Brush Park,” Finegood told me.

Richard Hosey, a developer who has helped revive downtown Detroit’s Capitol Park district, echoed that.

“I think it’s a very big deal,” he said.

Crucially the historic tax credit can keep parts of Detroit affordable for lower-income residents. Keeping Detroit affordable requires upgrading older buildings in the neighborhoods far from downtown. The only way to do that is to hold down development costs that get translated into rent once the project opens.

“It’ll be particularly important as we get to certain buildings in the neighborhoods,” Hosey said. “The more debt load and developer equity it takes to get a building done, the higher the rent has to be to make that building viable.”

Considered in isolation, the loss of the federal historic tax credit might be just another item to balance the nation’s budget. But taken in tandem with all the other changes in the Republican plan, a more sinister picture emerges.

The Republican plan also hits hard at major universities, which GOP lawmakers view as bastions of liberal thought.The plan would tax the investment income raised in the endowments of the largest and richest universities.

And the plan imposes a new tax on the highest paid executives of top universities and other non-profit entities, viewed as mostly liberal organizations, even as it eases the rules against political activity by churches, viewed as more conservative voices.

Read more:

A simple tax cut isn't all that simple, depending on your financial situation

Comerica economist: U.S. recovery could go into extra innings

Then, too, the proposed end to the deduction of state and local taxes and the proposed limits on deducting a home owners’ mortgage interest for the most expensive homes both hit hard at Democratic-leaning states like New York and California where home prices and taxes are high.

But it’s the zeroing out of the historic tax credit that most clearly signals the Republican intent. Cities like Detroit, Cleveland, Boston, St. Louis and dozens more harbor millions of Democratic voters. It’s hard to interpret the end of the historic tax credit as anything but a message that those cities and their residents matter less than big corporate interests that are the winners under the GOP plan.

A bit of good news: Michigan once had its own state historic tax credit used in tandem with the federal credit but it was ended in 2011 as part of the state’s tax changes. Legislation has been introduced in Lansing to recreate the state historic tax credit. Should the federal historic credit end, a state tax credit could take up some of the slack.

But that may be small solace if the Republican plan is ever enacted in full.

Lawmakers in Washington once recognized the importance of urban areas to the nation’s overall social and economic health. Ending the federal historic tax credit signals that lawmakers in Washington no longer think cities deserve any consideration.

Contact John Gallagher: 313-222-5173 or gallagher@freepress.com. Follow him on Twitter @jgallagherfreep.