Law enforcement estimates show that the nation has far more than 200 million guns in circulation. This means the black market has a pool to draw from that will be in place for decades. D.C. also found that new guns flowed into the city from Maryland, Virginia and other states where laws were less restrictive.
During the violent crack wars in the 1980s and early 1990s, the drug dealers depended on guns as the tools of the trade to resolve disputes, to police operations and to murder witnesses. Little has changed, and this problem is going to remain chronic until leaders and communities decide to truly and meaningfully address it.
One might comfortably ask why the nation allows such carnage. Is it because of who is dying in the largest numbers, percentagewise?
Thursday's court decision might be an important moment to give the country a reality check. The murder rate has declined from its high level of the crack wars, but more than 120,000 people have been murdered in the United States in the last decade.
ABC News' Theresa Cook and Randy Gyllenhaal contributed to this report.