We don't flee troubled places so much as we seek opportunity. The story of migration is one of pull, not push. The story of brain drain is one of push, not pull. Policies designed to retain talent misunderstand why people move:

At first glance, it might be imagined that the people most likely to migrate would be the poorest. However, the poorest people cannot afford it. Africa's Sahel, the world's poorest region, has not had emigration rates commensurate with its extreme poverty. Finance constraints give rise to an apparent paradox: An increase in income in the country of origin can actually increase emigration from it.

If a migrant's family is financing the costs, and benefiting through subsequent remittances, it is possible that the decision to migrate is not truly a decision of the migrant but of the migrant's family. Many studies support this depiction. In effect, rather than people choosing to change their country, families are choosing to become transnational. Families in poor countries are the mirror image of companies in rich ones. While the multinational companies are predominantly anchored in high-income countries, the multinational families are predominantly anchored in low-income ones.

The folks with the most incentive to leave, can't or won't. This bit of tragic irony is talent migration paradox number 1. The poorest places have the lowest rates of emigration.

Talent migration paradox number 2:

"The cities that people most want to escape are also the ones that people most want to come to." Even with high housing prices, polluted air, and increasingly crowded living spaces, China's metropolises continue to tantalize, and more people are coming than going. But many who arrive in the metropolis find they can only survive, not thrive. To (truly) be or not to be in China's big cities — that is the question.

The richest places have the highest rates of emigration. To get better returns on their labor, workers will put up with horrible living conditions. Once you can afford to go, you get out. The good life is elsewhere.

Where do the impoverished need to move? To cities with high housing prices. This is how economic globalization restructures the urban geography of the United States. Global forces are responsible for racial and class segregation.

With all of the above in mind, the U.S. Department of Housing and Urban Development (HUD) appears content to play small ball:

To facilitate this new approach, HUD will provide states, local governments, insular areas, and public housing agencies (PHAs), as well as the communities they serve, with data on patterns of integration and segregation; racially and ethnically concentrated areas of poverty; access to education, employment, low-poverty, transportation, and environmental health, among other critical assets; disproportionate housing needs based on the classes protected under the Fair Housing Act; data on individuals with disabilities and families with children; and discrimination. From these data, program participants will evaluate their present environment to assess fair housing issues, identify the primary determinants that account for those issues, and set forth fair housing priorities and goals. The benefit of this approach is that these priorities and goals will then better inform program participant's strategies and actions by improving the integration of the assessment of fair housing through enhanced coordination with current planning exercises.

The proposed data are insufficient for the task of assessing the segregation problem. As I've recently written, racially and ethnically concentrated areas of poverty may or may not be an issue. Where's the analysis of demographic dynamism? We can and should do better.