Most of the time, people think of a nation's capital as the epitome of its stability and constancy. Although governments don’t tend to shift their seats of government to a new city very often or on a whim, a capital sometimes is relocated from a border city to one deeper in the heart of country. When a capital is moved toward the center of a country -- usually toward an undeveloped region -- it’s known as a forward-thrust capital.
Usually, governments reseat their capital city to a forward-thrust capital to spur economic growth and development in undeveloped portions of the country. The move toward an expanding frontier region -- thrusting forward, so to speak -- is the traditional direction for countries to move their capital, although a forward-thrust capital may simply be one moved for the sake of economic development. Growth of capital cities typically spurs infrastructure development and economic growth in the area in which they’re built, helping to spark development in a frontier area.
Most countries move a capital toward the interior to spur development inside the country, but it’s not the only motivation for a forward-thrust capital. Other countries move a capital to a central location to normalize growth so that the nation develops at the same pace in different areas. Sometimes, it’s a symbolic gesture to indicate that the government doesn’t favor specific regions. At other times, it’s a move made for security -- positioning a capital away from a vulnerable place near a border to one that is more protected.
When Brazil decided to move its capital from Rio de Janeiro to Brasilia, the move was motivated to spur growth in the country’s underdeveloped western sections and pull populations away from the dominant eastern coastal cities. Pakistan relocated its capital from Karachi to Islamabad to be closer to Kashmir, a region claimed by Pakistan and India, as well as to shift development away from the south to the more economically active northern region.
Most capital cities tend to attract greater growth than other regions of the country. When a country wishes to spur growth in other areas or normalize economic development, it may instead create a regional development agency, establish growth poles with a key industry to attract growth in the underdeveloped region, or decentralize national government, spreading its workers and the economic benefits of the government's presence to several locations around the country.