I'm meaning for example why do some British people get upset when folks from the commonwealth want to move to Britain or some French people get upset etc..... after all the connection and the link is very much there?
Hoist by their own petard. It all stems, not only from the colonization itself, but the laws put in place afterward (British Commonwealth, former French colonies, etc. all have laws making their ex-colonials, eligible for immigration)
The whole idea of colonization was to get as much as possible from the colonized country. People from those countries, feeling a connection to the colonizing country, then return and make claims to be treated as citizens or equals to the colonizer, hence demanding that something (rights? opportunities? jobs? whatever) be given to them. Naturally this causes a problem for the colonizing country that was only interested in profit, not equality.
Because they bring their third world ways with them .
