People have drastically different worldviews. Those are beliefs that are cognitive foundations and are virtually impervious to logic or anything else.
I think part of the problem is that worldviews go along with group membership. So I think if there is going to be an improvement it will involve somehow modifying the group dynamics, which will have a surprising effect on the viewpoint divergence/convergence.
Some people also become emotional which leads to what you are likely talking about -colloquial irrationality. This idea itself can be a dangerous part of the problem, by assuming the other side is not rational, especially when you have multiple factions supporting the same idea but stating different reasons or participating in "irrational" behavior.
Also, the world views do not need to converge on every issue. It's a very western idea that when two sides are debating that one must be right and the other is wrong. Some eastern philosophies believe that the truth is in the middle. If we can discuss topics in a civil manner, we may be able to find common ground on many topics and subscribe to a less invasive mindset (many laws seem to be motivated by "I don't want [those people] to be allowed do [that]").
If world views really must converge and are not based on rationality, then we've all lost already and should divide the country (separate nations, urban vs rural) so the people can govern themselves according to their respective values.
Even if we modify group identities, to try to get world views to converge, in order for that new consensus to be valuable we still need the values that I list in my previous comment. Not to mention, even if we get those values to converge temporarily, they are likely to diverge in the future (are there any large countries that have a consensus worldview and that it has been stable? I don't know of any).