There are only two forces that unite men - fear and interest.

Fear and shared advantage are the two most dependable bonds and the coldest, and stopping there leaves out love, loyalty and belief, which have held plenty of groups together. Where it is accurate is in that reliability: danger and gain bind people with nothing else in common, and unbind them the moment either one moves. Anything built on only those two carries a shelf life.

Look at a group you depend on and ask what is genuinely holding it together. If the answer is only fear or only gain, expect it to loosen as conditions change. Something warmer takes longer to build and it survives circumstances.