However, Pollack said the ban proposed by Obama can help reduce gun violence, especially what he called the psychologically impactful mass shootings such as the Newtown attack in which a lone gunman used a Bushmaster semi-automatic rifle.
The combination of such weapons with high-capacity magazines "facilitates mass homicides," Pollack told CNN, noting that professional criminals generally don't use such rifles that look like military weapons.
"The people who do use these weapons are often the most dangerous or most sociopathic," Pollack said. The Newtown shooter, a 20-year-old man living with his mother, took her legally owned guns and killed her before going to the school to open fire on students and teachers.
To Pollack, such a mass killing -- while relatively rare -- "traumatizes communities and the entire society in a way that demands attention."
Studies show that street crime such as shooting deaths cost communities more than lives, Pollack said, citing emergency medical services and criminal investigation as tangible costs along with intangibles such as residents moving away to escape the threat.
Obama also made that point in his remarks on Friday, saying "it's very hard to develop economically if people don't feel safe."
In the aftermath of the Newtown shootings, the NRA called for putting armed guards at every school, rather than seeking to limit the ability of people to obtain weapons. It also wants tougher enforcement of existing gun laws, which Pollack agreed was necessary.
"A lot of the underground gun market could be stopped if we treated guns with the same amount of determination and tools as the drug market," he said.
For example, Pollack noted how committing a crime with a gun brought additional charges, and he called for similar treatment for illegally possessing a firearm.
In a Google Hangout online chat on Thursday, a participant asked Obama how renewing the assault weapons ban would help reduce gun violence caused primarily by handguns.
He responded that his proposed package would affect handgun violence through the expanded background checks and cracking down on straw purchases. Renewing the weapons ban focused on what Obama called "weapons of war."
"It's not going to solve every problem," the president continued, noting that some restrictions are already in place.
"We can't purchase a grenade launcher from a store, although there may be some folks who want to buy those," he said. "And the reason is we think on balance, the Second Amendment does not automatically assume that any weapon that's available you can automatically purchase."