strenuousness

noun

1. (uncountable, usually)The state or character of being strenuous; active zeal.

   “Here the debate might have moved into the political arena. For it has been clear over the past two years that the British Home Office and police do regard PIE as a corrupting organization. Hence the strenuousness with which they prosecuted this case — using a law which has, for some years, been condemned by many British legal authorities as unsafe and undesirable.”