Of course, terrorism should have the best people in the business - because of the enormous damage that can be inflicted.
Just as important though - is interagency cooperation and information sharing.
In the US, despite excellent manpower - and trillions of dollars - this has frequently been found lacking.
The DEA, NSA, FBI, CIA, NASA etc. often plough their own furrow - to their cost. 9/11 May be a prime example.
Hopefully MI5, MI6, Scotland Yard, GHQ etc. are more in tune - and sharing their experiences, operations and data.
Although there seems to be little evidence of it...