Bollards

Bollards are a cheap, simple and effective defence against attacks using vehicles, currently all the rage amongst Islamic terrorists in the West.

Bollards would have prevented most the of the deaths and injuries in the Parliament House attack in London. Sadly, the fashion for vehicle attacks was well known by that stage but the authorities in London had done nothing about that obvious target.

Here we see the effectiveness of barriers in one of two attacks, the Cambrils attack:

While details remain sketchy, it seems the Cambrils van overturned after hitting bollards or security barricades, at which point the occupants piled out and began shooting.

Source: The New Daily

Could Barcelona have been minimised using bollards?