A ban wouldn't make it hard to what?
One for the misnegation files — Leah Libresco, "Guns Like The AR-15 Were Never Fully Banned", FiveThirtyEight 6/14/2016:
The review for the DOJ concluded that bans on specific models or features of assault weapons had little to no discernible impact on gun deaths. If the law had any effect, the report said, it was most likely the result of bans on large-capacity magazines, which contain 10 or more rounds. (Large magazines allow shooters to keep firing without pausing to reload, a point at which their targets could run or fight back.) Calculations based on homicide reports in Jersey City, New Jersey, suggested that restricting large-capacity magazines might lower the number of gunshot victims by up to 5 percent. However, there are a huge number of high-capacity magazines already in circulation. The report authors concluded that a ban on them probably wouldn’t make it hard to keep a determined shooter from legally buying a pre-ban magazine and pairing it with an AR-15 equivalent.
[h/t Rick Rubenstein]