The militarization of law enforcement has been happening for decades.
By most accounts, the Ronald Reagan-era War on Drugs started the buildup of military weapons and tactics in local police departments.
Weighing the right police response to a particular emergency can be delicate, and there are police managers around the country keeping tabs on the blowback from police tactics in Ferguson, where unarmed African American teen Michael Brown was shot to death by an officer.
A lot of time and effort is devoted to training San Diego-area law enforcement to respond appropriately for that very reason.
Across the county, agencies work with 11 special weapons and tactics units (SWAT teams). They wear helmets, fatigues and bullet resistant vests, and they carry higher powered weapons to carry out specific missions.
“A SWAT team would not be appropriate for deploying for crowd control unless, of course, it was an issue of life and death,” Chula Vista Police Captain Lon Turner said.
Chula Vista has its own SWAT team but uses it "mobile field force" for crowd control.
“A mobile field force member would likely be carrying a baton and a shield,” Turner said. Members look more like police officers and less like soldiers.
Ferguson protestors-- some of whom were armed with bricks and bottles -- faced flash bang grenades, rubber bullets and tear gas from officers with battle-hardened appearances.
“Depending on how they're dressed can have an impact on how folks relate to them,” Turner said.
His mobile field force is dressed defensively with helmets and chest and knee pads.
“They have special gear, special training to either help disperse crowds that might be forming to commit unlawful activity or to help deny areas,” said Turner.
They can also help in evacuation and wildfire emergencies. The mobile field force mission is to control, not conquer.
Decommissioned military gear has been handed down to police departments for over 20 years. Some departments have gotten armored vehicles resistant to explosive devices and mines, while others have gotten get automatic weapons, fatigues and ballistic armor.
Military style gear has also been purchased with homeland security grants from the federal government since 9-11.