W​‌‍‍‍‌‍‍‌‍‌‌‌‍‍‌‍‍‌‌‍​hat defines critical infrastructure and key resources? Specific to the threat of terrorism related to the​‌‍‍‍‌‍‍‌‍‌‌‌‍‍‌‍‍‌‌‍​se critical assets, can you describe the possible motivations for those carrying out terrorist activities​‌‍‍‍‌‍‍‌‍‌‌‌‍‍‌‍‍‌‌‍​?