This is a story that is notable for the bragging that is done on the discretion of the German polizei, or police. I think it is fairly safe to say that the bragging is justified.
A few misconceptions should be dispensed with. German police are always armed. Always. Every police officer that I have ever seen had a weapon. They look remarkably like the police do in the United States, except for the fact that they drive station wagons. So, what we are seeing here is a very discreet use of force.
The firepower, in hand, of the German police is actually substantial. They have access to a great deal of weaponry and have had to deal with a great deal of civil unrest in recent years. Last year, some 30,000 politically motivated acts of violence were also registered. And yet, there is a low incidence of the actual firing of weapons. Non-lethal means of subduing people are employed here to various results.
What are they up against? They are up against a heavily-armed populace.
That's a significantly high rate of gun ownership. German society is not pacifistic but it is overwhelmingly law-abiding (most of the "illegal" guns are older antiques, I would think). And the Germans made a unilateral decision recently to stop Americans from bringing their own guns here:
Why? No one knows. And I'm not sure if it has been lifted, but it does speak to how they regulate criminal behavior here--they prevent it from happening. But, perhaps, it was done to stop illegal guns from coming here.