That's contraction and not expansion
Theme
Three causes of European expansion are; economic causes, internal political stresses, international tensions.
Comparative economic systems is the subfield of economics dealing with the comparative study of different systems of economic organization, such as capitalism, socialism, feudalism and the mixed economy.A historian who compares the expansion of political system to the expansion of economic system is organizing history by theme.
The expansion of slavery into the territory west of Missouri
Supported expansion
Territorial expansion raised the question of whether new lands should be free or slave.
Stephen A Douglas
The political issue behind the question of expanding slavery after the Mexican-American War was whether the newly acquired territories would be free or slave states. This debate ultimately led to the Compromise of 1850, which temporarily resolved the issue by allowing some territories to decide on the issue of slavery through popular sovereignty.
Compromise Act of 1850
The beliefs of the Japanese militarist political movement are so many. Most of them revolve around nationalism, politics and military expansion.
The question of whether to allow the expansion of slavery to the territories