The problem is that at the same time they are trying to force people to do what some think is "right", they are trying to remove the final arbiter of right and wrong who exists beyond the ability of people thus has the last word on the subject and we, the people, then have to deal with it and move on.
Yes, that would be God, the Creator of all things, Mother Nature, name it what you will, it's the same higher authority.
People can make laws causing a behavior or an action to be considered legal or illegal, meaning, it is to be tolerated in society to a certain degree or it will not be.
However, we can, or should all be able to see that something that is "legal" is not necessarily the same thing as being "Right" just as something that is "illegal" is not always going to be the same thing as "Wrong".
For example, most people might likely agree that although it is legal for a lender to foreclose on a back-owed property, when said person is owing has just lost their job, has a family and is just barely able to get food on the table, it isn't likely to be considered as "Right".
Consequently, someone witnesses a nare-do-well attempt to brutalize an old woman in broad daylight and take her money, it is "illegal" for that witness to walk up out of nowhere and do harm to that criminal with extreme force. Yet, there are many who would say that the witness did exactly what was "Right" in stopping the criminal with extreme prejudice.
There are many other countries who try to legislate morality telling the people what is "Right" or "Wrong" and that their laws reflect that (whether they actually do or do not.) However, almost all of those other countries have a much different type of government which does not hold individual liberty as the core or the base of society. It is their own view of morality they are forcing everyone else to observe.
In trying to say that the United States of America should be like other countries in doing something in regards to legislation, it must be remembered that the U.S. is in certain core, basic ways, very different from any other country and those comparisons are incorrect and inapplicable.
The U.S. rejects the idea that there is one single moral perspective for everyone and that every individual has the god given liberty to exercise their own judgement.
Because of that individual liberty and respect for a variation in moral perspective, the U.S. is a country that operates under the rule of law.
The laws are there, or are supposed to be there, to protect individual liberty and to protect the rights of every individual. Thus, ideally, the laws are supposed to be written to consider the person who intrudes upon the rights of another as criminal when they commit an act that causes harm to another person.