"You have people who have committed these tragedies who would not have come to anyone's attention," said Sue Abderholden of the National Alliance on Mental Illness. "They wouldn't meet our commitment standards. They weren't in trouble with the law.
"Half of all adults who have a serious mental illness experience symptoms before the age of 14. So we should be intervening early, right away with the intensity that's needed," she said.
President Obama's proposals on gun violence include hiring more school counselors and mental health experts, expanding aid to states for better record keeping and participation in the background check system, and giving clearer encouragement to doctors to report credible threats of violence by their patients to police.
Some budget hawks in Congress have expressed concern over the cost of the proposed mental health care approach to gun violence, and how its impact would be measured. Experts concede the strategy would take a long time and is far from foolproof.
There is also still a yawning gap between gun control and gun rights advocates over a proposed expansion of background checks to gun shows and private sales, and a plan to ban assault-style weapons and accessories.
But Stanek and other advocates of his view the effort is worth it if officials can prevent just one tragedy from happening again.
"People need to keep hammering away and do the fixes that we suggested," he said. "Even if it's piecemeal and baby steps."
ABC News' Sunlen Miller contributed reporting.