Much of Western Europe allows religious freedom, but social organization has obviated the need for religion. Most people are unbelievers, or give the matter little thought.Religion separate from state control provides a degree of social cohesion, a sense of communal belonging through shared rituals,common aims. On an individual level it motivates people to make moral decisions, obey laws, contribute to the communal good and gives people a sense of direction and purpose.
Western Europe is a good case- it is overwhelmingly Christian in culture- many political parties in Europe are Christian democrats and religion is a major feature of European societies.
If we stick with Eastern bloc countries they have mostly overthrown their Communist/atheistic governments and now allow religious freedom for people of all faiths.
They overthrew their Communist dictatorships because they were not working on economic or political levels. I hope I've answered your point.
Religiosity seems inversely proportional to security.