To unite or not to unite?

Organization A was set up in the 1960s in Singapore. It sells gadget X to market sector Y in Singapore. And it has links with organization B in Thailand. Organization P was set up in the 1990s in Singapore. It sells gadget X to market sector Y in Singapore. And it has links with organization Q in Thailand. Both organizations A and P uses the same marketing strategy. Bearing in mind that the products, customers and marketing strategy have much resemblance, it is mind-boggling that the two still cannot merge. And it is also surprising to see that even though their works are rather similar, and that they both have links with Thailand, they still link with different organizations in Thailand. Why can they not merge and form one big organization? Does the problem lie with organizations A and P, or does the problem lie with organizations B and Q in Thailand? Mind-boggling..... And to think that I have to come out with a potential solution.... hmmmmm.....