IANAL, but I entrapment can occur when law officers enticies the suspect to commit a crime the wouldn't normally https://en.m.wikipedia.org/wiki/Entrapment

The definition of "wouldn't normally" looks like some hairy case law, but it isn't as simple as you are saying. If they are offered a bomb for sale after a lengthy conversation about how great terrorism is and how important it would be for them to take the bomb, you could possibly have an entrapment case for example.