28 cultures is quite a lot of diversity to suddenly and forcibly slam onto a single party-line. Have you considered that maybe this collection of cultures might have values and methods that are sufficiently mutually different, that there often isn't a single policy that will satisfy all of them?

Here in the USA we have an analogous situation, but it is maintained - for at least a century and a half - with enough top-down brute force to keep the resulting tensions simmered-down such that they are only expressed via things like the "culture wars" phenomenon.