Mar-a-Lago estate in Palm Beach, Fla. (Kevin Lamarque/Reuters)

Back in the 1970s, the CIA developed what we would now call a drone that was designed to be disguised as a dragonfly, called the “Insectothopter.” According to Spycraft: The Secret History of the CIA’s Spytechs, from Communism to al-Qaeda, there is a DARPA model of a similar surveillance device no larger than horsefly.

The Chinese woman who was arrested after gaining entry to President Trump’s Mar-a-Lago resort almost succeeded with a much simpler approach: Just carry around a thumb drive and wait for the authorities who arrest you to plug it into their computers.

The Secret Service agent who questioned Ms. Zhang after her arrest, Samuel Ivanovich, said during testimony that she did not carry any lock-picking or eavesdropping gear. His four-and-a-half hour interrogation of Ms. Zhang was recorded by video, Mr. Ivanovich said, but it lacked sound because he didn’t realize that the agency’s office in Palm Beach didn’t have that capability. Mr. Ivanovich testified that the computer analyst who reviewed Ms. Zhang’s devices said that the thumb drive she was carrying had immediately begun installing a program on his computer.

“He stated that he had to immediately stop the analysis and shut off his computer to halt the corruption,” Mr. Ivanovich said.

First, who outfits an interrogation room with video recording but not audio recording?

Second, what computer analyst puts a thumb drive from a suspected spy into a computer and doesn’t expect malware?

Securing a site like Mar-a-Lago is no doubt extremely difficult: It’s large and involves many members of the public coming and going. But this incident is rather embarrassing for the Secret Service, and probably is a factor in the impending change in leadership.

Finally, can we bring back the Insectothopters? If nothing else, it would be fun to watch America’s enemies growing paranoid that every dragonfly or horsefly around them is secretly watching and listening to them.