It's not necessary to take all guns away from people in the US. There is a large and avid hunting community for example. At farms and ranches in very remote areas, people use guns to control predator and pest populations (coyotes, for example). Also because they live at the end of a remote country road where there are no law officials within reasonable response time they have them for self defense.
Canadians have adequate gun laws that enable people with a legitimate reason for owning a gun to do so without flooding the country with mass killing machines like the AR-15 and hand guns. It doesn't sound like New Zealand is contemplating a full on gun ban but probably will tighten restrictions on military-style weapons of mass murder.
@Roger A. Shrubber , there is no way that one person with a knife could have killed 50 people and put another 50 in the hospital in his 10 minute murder spree. Also the Las Vegas killer would have had a hard time hurting anybody from his window in that hotel. Regulating guns isn't an answer to mankind's propensity to kill each other but it sure does cut down the number at risk. Also, using a knife is not simply a matter of walking into a room and opening fire like the mass murderers with their semi-automatic rifles do.
That said, the times that a determined murderer used a car or truck shows that you are right in that mass killings won't end with gun regulations. I just want to see the US gun homicide rate approach that of other developed countries like Canada, Australia, New Zealand and Britain. I think that is the objective gun regulations, not ending all mass murder although I wouldn't oppose that.