It depends on the law. Take the fourth amendment. It doesn’t prohibit searches and seizures. It only prohibits “unreasonable” searches and seizures. Or the fifth amendment. It doesn’t prohibit depriving someone of life, liberty, or property, but permits it subject to due process.

Other provisions are less loosey-goosey. The first and second amendments are categorical prohibitions. You can’t establish a national religion even if you think the results will be tremendously beneficial. The taxation clause is similarly clear. We needed an amendment to create the income tax, even though it was necessary to a modern state.