Here’s another essential quality in a resistance leader: courage, or holding steady through anxiety.

Resisters knew they had a lot to fear. By the end of the war the occupation authorities followed a policy of ruling the population through terror. To that end they took hostages from among the civilian community and publicly executed them when German soldiers were assassinated. They made no secret of the fact that they tortured men and women. They did not hide that they deported political prisoners to camps in the Third Reich, although they did hide what exactly happened in those camps to make them more frightening.

Resisters were afraid, if not for themselves then for their families. But they acted anyway. How they did so was probably different for each individual, but it was not the sort of thing that was asked about or discussed in the documents.

I did, however, have the great privilege of talking to a woman who guided hundreds of aviators across the Netherlands, a few of whom ended up with Dutch-Paris.

She told me that she was careful. She would watch for anything out of the ordinary. She would listen for anything out of the ordinary. She would even inhale deeply before turning a corner because German soldiers smoked a higher quality of cigarette than civilians could get. If Germans were smoking ahead, she could smell the danger.

But even so there were many times when she was scared and anxious. At those times she would give herself a stern talking to and get on with what needed to be done. That’s how she held steady through anxiety to rescue hundreds of downed Allied aviators. It’s what enabled her to show great courage.