Veteran journalist Geraldo Rivera isn’t taking President Trump at his word — not literally, at least — insisting he’s greatly exaggerating the total destruction of Iran … something he believes the Pentagon wouldn’t allow.

The longtime news anchor joined us Tuesday on “TMZ Live” to discuss Trump’s proclamation that a “whole civilization will die tonight” … in reference to his promised bombing of power plants and other civilian structures if Iran doesn’t agree to a ceasefire by 8 PM ET.

Geraldo says he thinks the president’s just being bombastic … something he’s seen up-close and personal with Trump during his time on ‘Celebrity Apprentice.’

It’s “alarming” language, Geraldo admits … but, he’s sure the Department of War would never authorize strikes on civilians, like would be required to destroy the entire civilization. Geraldo also doesn’t believe Trump plans to use a nuclear weapon.

Geraldo admits war is an imperfect way to promote democracy in Iran … but the Iranian regime has to go — and he says force seems to be the only way to do it.

Harvey and Charles were skeptical about the Iranian people embracing any campaign to upend their civilization … but Geraldo thinks they’ll welcome U.S. armed forces with open arms. Watch the clip all the way through to hear why.

Trump has used quite a bit of harsh language in recent weeks … putting out a profanity-laced tirade on social media and promising to bomb the country back to the “stone ages.”

Geraldo says he can’t see the prez doing it … but we’ll just have to wait and see … clock is ticking.