This empathy-less prosperity gospel also permeates attitudes about the role of our government. Consider when Housing and Urban Development Secretary Ben Carson said in March that poverty was a “state of mind.” Representative Mo Brooks of Alabama echoed this in a May interview when he said that “people who lead good lives” don’t have to deal with pre-existing medical conditions. This kind of thinking by the Republicans, that individual effort and religious faith are paramount, has desensitized them to poverty, disaster and the vagaries of disease. They have already cut millions from federal disaster aid, and if an uptick in disasters occurs, many more people will die.

Mr. Trump and Mr. Osteen aren’t the first to display such tone deafness. President George W. Bush, an evangelical known for his “compassionate conservatism,” was crucial in promoting an individual ethic of compassion. “Government cannot solve every problem,” Mr. Bush said in 2002, “but it can encourage people and communities to help themselves and to help one another.” What that really meant was churches, rather than the government, needed to administer social aid programs. The self-reliance of individuals and communities would substitute for federal support.

So while the storm churns through Texas and Louisiana, causing floods, death and misery, it is time to consider the damage the prosperity gospel has done to America. Mr. Trump and Mr. Osteen unwittingly revealed its ugly underbelly: the smugness, the self-aggrandizing posturing. It has co-opted many in the Republican Party, readily visible in their relentless desire to strip Americans of health care, disaster relief and infrastructure funding.

Now Ted Cruz and Texas Republicans seek federal disaster aid, although they voted against the same in the aftermath of Hurricane Sandy. The Republicans in states affected by the disaster will find out soon enough what it feels like to come to Washington and relief organizations with their hat in their hands.

The survivors of Hurricane Harvey do not need empty tweets and platitudes from people like Donald Trump and Joel Osteen. They have shown beyond a shadow of a doubt that, as we say in Texas, they are all hat and no cattle.