Translation of the question: 1) what would happen if in Colombia exist only one region? 2) would it be good for democracy that a single party governs?
Colombia, as well as many South American and worldwide countries, function under the model of a democratic federation, where each department ( named in other countries as states, provinces, etc.) have sovereignty and are all gathered by a federal government that unifies them into a nation. Each region of any country and Colombia is not the exception, has their particularities, some of them are richer and more developed than others, some are wealthier, while others are poor.
The idea of a unification though, desirable in theory, do not allow these regions to express their particularities in culture, ethnic, economic and sociopolitical manners or beliefs, therefore sharing the common through the federation, but their peculiarities through the differentiation of several departments of regions allow social and political stability to be possible.
For the same reason, in terms of democratic government, different voices (and different ways of thinking) are necessary to include in a balanced manner all their political preferences, having in mind that in a democracy ( the govern by the people) none exerts absolute control, and no one imposes all their beliefs over the other, but establishes agreements among the different parties to satisfy the needs of the country, looking at common interest on behalf of the state. The hegemony of a single party is as harmful as a totality govern. An excellent example of this is Mexico, where for 70 years an only party ruled the institutional revolutionary party (PRI) which caused the lack of counterbalance in the policy and segregation of opposition to the regime.
