When you have kids, you start looking around for all the harmful things they might do by accident, like stick a finger in a socket, drink cleaning fluids from under the sink, climb out a second-story window, fall down some stairs, or drown in a toilet, and so on.
And you install devices — covers, locks, gates, caps — to keep those things from happening.
And you do it before you’re overwhelmed by sleep deprivation or other forms of stress. While you’re still able to think calmly and clearly about the future.
That’s the basic idea behind a constitution, and especially a bill of rights. They are devices installed by adults to keep children from doing things that would cause great harm — like passing laws to abridge freedom of speech, infringe the right to keep and bear arms or deprive people of their livelihoods in the name of public health — because they just don’t know any better.
That is, a constitution, and a bill of rights, are essentially child-proofing devices.
