I have spent my whole career, in MI5 and now as head of GCHQ, working to counter the most serious threats to our national security. If I’ve learned one thing it’s that our adversaries are quick to spot new ways of doing us harm. We see that in the way terrorists are constantly changing their weapons or states are using their full range of tools to steal secrets, gain influence and attack our economy.

The biggest changes are shaped by the speed of technological advances, in particular the internet. These shifts are affecting virtually everyone on the planet. They offer amazing potential for individuals, communities, business and countries – friends and foes alike.

Our task in GCHQ is to help make sure that the UK benefits from this technological revolution, by protecting the nation from those who want to use the internet to cause harm. We all derive great benefit from the ease and speed of connecting across the planet and from the additional security provided by default encryption. But hostile states, terrorists and criminals use those same features – instant connectivity and encrypted communications – to undermine our national security, attack our interests and, increasingly, commit crime.

We see these threats to the UK’s prosperity and security changing faster than most people realise. But GCHQ – at the heart of the nation’s security – is an ingenious organisation. In my six months as its Director I have seen countless examples of what can be achieved with a brilliant and diverse group of people using cutting-edge technology and tradecraft. We are part of an operational community of MI5, MI6, the police (particularly the National Crime Agency) and our Armed Forces – a combined force of thousands of men and women dedicated to Britain’s national security who now work far more closely together than at any point in my career. These collective capabilities are a huge strategic asset to the UK.