Republican presidential candidate Ben Carson is challenging his fellow Republicans to call last week’s Charleston church massacre an act motivated by racism.

In an op-ed published in USA Today on Monday, entitled “Call it racism,” Carson argued that not every tragedy or massacre is motivated by race. But when every sign points towards racism, then “it just is”:

“So when a guy who has been depicted wearing a jacket featuring an apartheid-era Rhodesian flag allegedly walks into a historic black church and guns down nine African-American worshipers at a Bible study meeting, common sense leads one to believe his motivations are based in racism.”

Carson went on to compare the reluctance of some to link the massacre to racism to a doctor not correctly diagnosing his patients:

“When you wait too long to identify the problem, you miss your best chance to stop it.”

The Hill added that Carson called out fellow Republican presidential candidates Sen. Lindsey Graham (R-SC) and Jeb Bush for not immediately attributing the attack to racism:

“There are people who are claiming that they can lead this country who dare not call this tragedy an act of racism, a hate crime, for fear of offending a particular segment of the electorate

I understand the sensitivities. To some, calling the events in Charleston, S.C., a hate crime reinforces a stigma, which they have fought hard to put behind them. But refusing to call it what it is — racism — is a far more dangerous proposition.”

It’s been confirmed that Dylann Roof carried out the attack because he was inspired by racism. Roof even went so far as to write a “manifesto,” in which he wrote down and examined several different races and offered insight as to why he “had” to carry out his attack.