The speed with which such a large number of signatories was marshalled in response seems very neatly to demonstrate the need for the original article.

Statistics are used to demonstrate the need for new legislation, or highlight the successes and failures of existing legislation.

Transition towns and ecovillages demonstrate the need for engineers to build systems that manage un-sustainable risks and provide people with sustainable options.

These tools further demonstrate the need to determine intent of those taking action to identify subversive activities.

But it demonstrates the need to think hard not only about the medical consequences of genomics, but the social implications as well.