Immigrants deprive nationals of jobs and increase unemployment and social security costs.
Following Hungarians, German descendants in Romania used to be the largest minority in the country. After opening the borders, and due to the repatriation immigration policy of Germany, their number drastically decreased. This migration did not invoke bold headlines, though, because these people were much less visible. Another sorts of migration are those that follow wars, collapsed economy systems and international conflicts (see recent examples of Rwanda, Sudan, Kosovo) or natural catastrophes, like the renewed volcanic activity on the island of Montserrat that resulted in a feverish evacuation of most of the inhabitants.
Immigrants do not cause unemployment of nationals, even among low-paid and minority groups. They take jobs but they also create as many jobs through the enterprises that they initiate. Immigrants do not benefit abusively from welfare services at the expense of nationals since they are typically young and healthy when they arrive and tend to pay more taxes than nationals. Immigrants are typically as well-educated and occupationally skilled as nationals and bring valuable technical knowledge with them, often at a post-graduate level. Immigrants demonstrate desirable economic traits, with a tendency to save more than nationals. Immigrants increase the flexibility of the economy since they are unusually mobile both geographically and occupationally. Immigration alleviates the problem of financing the social security costs of the elderly because they tend to be entering the prime of their work lives and their tax-paying years.
In theory, leaving one's own country belongs to the basic human rights even today. Whoever thoughts s/he can find better life in another country has the right to go and try. However, migration today has been made next to impossible by the existence of national countries with fragile economic and social systems that are jealously protected.