Trump did not recommend it's use. Trump talked about what medical advisers are working on just what he said. Other countries have already tried this. People seem to forget the words could be, maybe hopefully.
Trump is smart enough to put a very good, world class immunologist and ID specialist in Anthony Fauci in charge. And he'd be really smart if he'd not add his opinions to the mix. I get that he's an abnormal politician and does abnormal things. But he should really just go over what the plan is from a political perspective, then introduce Dr Fauci and leave everything else to him. Fauci is one of those rare people that both Democrats and Republicans will listen to. Trump should lean on this.