If you are curious about the trend of the militarization of the police I'd suggest reading "The Rise of the Warrior Cop" by Radley Balko.
One thing the book points out is that since the first SWAT team was formed in LA back in the 1960s, even law enforcement agencies with as few as 28 officers have SWAT teams. One of the things the author attributes this to is a "me too" attitude where one department hears another local agency has a SWAT team with special equipment and weapons. Somewhat jealously the agency decides they need one too. Even if the population they are serving has no history of the kinds of violent and/or dangerous crimes that normally require SWAT.
One thing the book points out is that since the first SWAT team was formed in LA back in the 1960s, even law enforcement agencies with as few as 28 officers have SWAT teams. One of the things the author attributes this to is a "me too" attitude where one department hears another local agency has a SWAT team with special equipment and weapons. Somewhat jealously the agency decides they need one too. Even if the population they are serving has no history of the kinds of violent and/or dangerous crimes that normally require SWAT.