Operators have to learn to recognise a threat and choose the right response — ideally in a realistic EM environment with Red and Blue roles. This is where something fundamental chafes, the spectrum paradox: in peacetime you are not free to disrupt the spectrum (Doctrine & EMSO, spectrum management and EMCON). Real jamming during an exercise would hit air traffic, civilian communications and friendly systems — and you would reveal your capabilities to listening adversaries.
That is why the emphasis lies on simulation and closed ranges, where the EM effect can be replicated without affecting the outside world. The price is a trade-off between realism and cost/safety — exactly the tension that structures the whole test ladder (The test ladder: from model to live).
Test, training and simulation close the circle of the whole course: doctrine (Doctrine & EMSO) sets the rules, the threat library (EW: Electronic Support Measures, New concepts in EW) holds the knowledge, and the systems (Electronic Counter Measures–EW: Electronic Support Measures) deliver the effect — but everything is only as good as the validation behind it. And because threats keep evolving (cognitive EW, New concepts in EW), testing is not a one-off step but a permanent race. For the EW specialist, "is my data up to date and tested?" is just as important a question as "do I have the right jammer?".