Trump Allegedly Fearful to Discuss UFO Info, Other Presidents Sketchy

There's something going on with U.S. Presidents and UFOs ... they've been briefed on the subject, but won't say anything publicly ... and Donald Trump seems scared of disclosure.

TMZ Studios has a new series, "Strange & Suspicious," now airing on a dozen FOX stations, where we explore strange, unexplained and downright weird stories, and former presidents' silence on extraterrestrials speaks volumes.

Trump sounds like he knows something YUGE when it comes to UFOs ... but he always waffles on the issue, at least on camera ... and there may be a reason behind his reluctance to spill the beans.

It's pretty alarming ... Australian investigative journalist Ross Coulthart says he's been told Trump is scared he will be assassinated if he shares the truth behind the UFO phenomenon.

Despite tons of whistleblowers and mountains of supposed video evidence of unidentified craft, no former or sitting president has ever said what they know about aliens.

You would think they would say there's no threat or no such thing as UFOs if that was the case, right?!?

Trump, Bill Clinton, George W. Bush and Barack Obama have all been asked the UFO secret files question on TV ... but Americans have never gotten a straight answer, which frankly raises a lot of questions.

So, what do they know and what are they hiding???