What is the likelihood of an attack on critical infrastructure by domestic terrorists

Domestic terrorist attacks, focusing on Water treatment systems, the power grid and agriculture. Should not be just a mere history. The paper should have a nexus to U.S. soil. This course is specifically about the Department of Homeland Security and should address factors specifically related to the subject area of homeland security. i.e the structure of DHS and current security practices protecting Critical infrastructure and their weaknesses that make them vulnerable to an attack. Should include a short summary page, introduction or problem statement, a conclusion statement. APA format Double spaced 1 inch margins