Donald Trump is waging a nonstop, all-encompassing war against progressive culture, in magnitude analogous to what 19th-century Germans once called a Kulturkampf.

As a result, not even former President George W. Bush has incurred the degree of hatred from the left that is now directed at Trump. For most of his time in office, Trump, his family, his friends and his businesses have been investigated, probed, dissected and constantly attacked.

In 2016 and early 2017, Obama appointees in the FBI, CIA and Department of Justice tried to subvert the Trump campaign, interfere with his transition and, ultimately, abort his presidency. Now, congressional Democrats promise impeachment before the 2020 election.

The usual reason for such hatred is said to be Trump’s unorthodox and combative take-no-prisoners style.

Certainly, Trump’s agenda of closing the border, using tariffs to overturn a half-century of Chinese mercantilism and pulling back from optional overseas military interventions variously offends both Democrats and establishment Republicans.

Trump periodically and mercurially fires his top officials. He will soon appoint his fourth national security adviser within just three years.

To make things worse for critics, Trump’s economy is booming: near-record-low unemployment, a record number of Americans working, increases in workers’ wages and family incomes, low inflation, steady GDP growth and a strong stock market.

Yet the real source of Trump derangement syndrome is his desire to wage a multifront pushback — politically, socially, economically and culturally — against what might be called the elite postmodern progressive world.

Contemporary elites increasingly see nationalism and patriotism as passé. Borders are 19th-century holdovers. The European Union, not the US Constitution, is seen as the preferable model to run a nation.

The media can no longer afford to be nonpartisan and impartial in its effort to rid America of a reactionary such as Trump, given his danger to the progressive future.

America’s ancient sins can never really be forgiven. In a new spirit of iconoclasm, thousands of buildings, monuments and statues dedicated to American sinners of the past must be destroyed, removed or renamed.

A new America supposedly is marching forward under the banner of ending fossil fuels, curbing the Second Amendment, redistributing income, promoting identity politics and open borders and providing free college, free health care and abortion on demand.

An insomniac Trump fights all of the above nonstop and everywhere. In the past, Republican presidents sought to slow the progressive transformation of America but despaired of ever stopping it.

No slugfest is too off-topic or trivial for Trump. Sometimes that means calling out former NFL quarterback Colin Kaepernick for persuading NFL stars to kneel during the national anthem. Trump goes after antifa, political correctness on campus, the NATO hierarchy, the radical green movement, Planned Parenthood and, above all, the media — especially CNN, The Washington Post and The New York Times.

For all the acrimony and chaos — and prognostications of Trump’s certain failure — a bloodied Trump wins more than he loses. NATO members may hate Trump, but more are finally paying their promised defense contributions.

In retrospect, many Americans concede that the Iran deal was flawed and that the Paris climate accord mere virtue signaling. China was long due for a reckoning. Special counsel Robert Mueller’s investigation proved fruitless.

Trump has so enraged his Democratic adversaries that the candidates to replace him have moved farther to the left than any primary field in memory. They loathe Trump, but in their abject hatred he has goaded the various candidates into revealing their support for the crazy Green New Deal, reparations for slavery, relaxed immigration policies and trillions of dollars in new free stuff.

In a way, the left-wing Democratic presidential candidates understand Trump best. If he wins his one-man crusade to stop the progressive project, they are finished, and their own party will make the necessary adjustments and then sheepishly drift back toward the center.

Victor Davis Hanson is a classicist and historian at the Hoover Institution.