They are already labeling him a white supremacist.
MS-13 members are very likely to be classified as nationalists, but for what nation? Certainly not the US, and they are not at all what is generally regarded as “white” in any way, shape, form or manner.
MS-13 members are mean to the core and bad to the bone, not for any ideology, or even for profit as in “it’s just business”, as the Mafia types are prone to say. They are just sadistic, brutal gang types that substitute violence for anything remotely related to sexual prowess, and have carved out a place for themselves in a special corner of Hell. They profess not to believe, but still pay great homage to the Prince of evil, and remain unrepentant and intransigent in the face of all reform.