Consider feeding 50 people at a restaurant versus doing so at home. At a restaurant everyone chooses individually which dish they would like to eat, generally from a select category, such as barbecue. There could be polar opposites in taste; for example one person might want pork, whereas another person might want brisket. All 50 people might want their own different dish. That is okay though because both can have what they want and the restaurant can flourish because no one is trying to order egg rolls. On the other hand if you try to feed all 50 people at home not everyone gets what they want because 50 it is unreasonable to make everyone their own dish. So instead there is a lot of compromise and fighting and in the end no one is truly happy. It is the same with laws in the United States.
To further explain the metaphor: Why is everyone so caught up having the same policies nationwide? Instead of the 50 people trying to be happy with dinner, there are 50 states that all want to have laws which represent them and their citizens. So if the federal government were to quit trying to make one policy set for all 50 states and instead let each state make their own, they could have 50 happy customers instead of none. As long as all of these customers stick to the same category (constitutional), everyone can be more satisfied.
Look for a moment at Texas. The majority of Texans are very big on interpreting the 2nd amendment as everyone should be allowed to carry their own gun. Californians on the other hand are vastly in support of an interpretation that only the state’s malitia (i.e. California National Guard) should be the ones with the guns. The Federal Government works to try to make a policy that makes both of these areas happy, yet neither will be happy until they completely have their way. So instead of one policy for both, each could have their own policy. Plus for the people who disagree with the majority of their state, there would be the option to move to a state more aligned with your views. As long as the constitution is not directly violated (i.e. no one can have guns) then both can be happy and the constitution is being upheld.
Additionally there is another case for states to make more of their own policies. If you look at the national congressmen, they all represent huge amounts of constituents and spend the majority of their time many miles from home. On the other hand, state congressman are never so far away from the constituents, of which there are less.
Conclusively: the federal government needs to take a step back and allow the states to make more of there own decisions. Each individual state can have policies that reflect its citizens exclusively, rather than an entire nation that might disagree.