Dozens of interviews with people deeply familiar or involved with the election process point to a clear consensus: Not only could Trump make a second attempt at overturning an election he loses, he and his allies are already laying the groundwork.
Archived at https://ghostarchive.org/archive/8e3Ri
It should go without saying that top military leaders and top spy agency leaders have considered what they might do under various circumstances.
Obviously it would depend on the details and we have no idea, but if Trump tries to brazenly push a coup, and it looks like it might be successful, you can imagine someone at the CIA considering whether they should fix the situation.
It’s a strange situation because we can only blindly speculate, but when people are trying to tell us that the sky is falling, it’s important to keep in mind that when you get to a coup d’etat, regular reasoning goes out the window. At some point, again depending on the details, it just doesn’t matter what the Supreme Court says.