Nobody needs 24/7 media coverage of mass killings. It leads to the copycat effect where unbalanced people are given an incentive to kill masses of innocents in order to become famous.
Nobody needs to go to the church of their choice. One state sponsored church is plenty.
Nobody needs to refuse police questions. What have you got to hide? This practice allows child killers to roam the streets.
Nobody needs to assemble in large groups. It is dangerous and leads to riots. Small children are trampled to death.
Nobody needs Automobiles. Mass transit is more efficient and safes the lives of children.
Nobody needs to videotape police. It hinders investigations and police efficiency.
Nobody needs alcohol. That did not work out so well last time.
Nobody needs marijuana. That is not working out well at present.
Nobody needs unsupervised Internet access. It leads to misinformation and political unrest. People would have access to dangerous information.
Nobody needs twitter or text messaging. Look at all the trouble it caused in Libya, Egypt, and Syria.
Nobody needs meat. People have to kill animals to get it.
Nobody needs more than one bathroom per house. Anything more wastes water.
Nobody needs swimming pools. Hundreds of children drown in them every year.
Our society is not based on the Marxist concept of “to each according to their needs”. Our society is based on the rights of the individual. Rights are protected by the Constitution, and are not subject to majority vote.
Banning a box with a spring that can be produced in any home workshop, when there are hundreds of millions already in circulation, would do nothing to stop mass murders. Even given the unlikely possibility that it could do a very little good, it would certainly do great harm. While you may not see the “need” for such a device, tens of millions of your fellow citizens vehemently disagree, as indicated by the millions that are being sold every month. They will resist such a law with more moral certainty than anyone resisted prohibition. Many lives will be lost trying to enforce such a provision. Either jails will be filled to overcrowding, or the provision will only be given lip service. Neither result advances the public good.
There is a reason that these provisions are pushed in the heat of an emotional response. They cannot stand reasoned reflection.