The first is to protect our security.
The rise of international terrorism, mass movements of people, the transformation in communications technology which makes it easier for terrorists to plan and co-ordinate their campaign.
All of these things make it harder for governments to protect their citizens.
And the security challenge is amplified by the willingness of today's terrorists to murder innocent civilians on a vast scale, using whatever weapons they can get their hands on - and being prepared to kill themselves at the same time
