Who will have to wear the armbands? The Danish people or the immigrants who want to come in?
Who is the “Danish People” and who are the immigrants?
That was a serious question in the context of the posted article.
The Danish government has continued to monitor people in Denmark, in recent years. They, often randomly, call people (Danish born and heritage) mostly those born outside Denmark yet to Danish parents to ask if they feel ‘integrated’.
That isn’t a bad thing as such.
But, those muslims or Islamists (whatever you call them) were Not born outside France or Beligum (Paris or Brussels — nor San Bernardino). They were born and raised inside France, Belgium and USA — sadly.
Point is, once you don’t and Can not differentiate, you’ll end up with a massive prejudice as did Nazi Germany with the Jews. Round them up.