What are the characteristics of an informal empire?

An informal empire differs from a formal empire in that, while the imperialistic country is able to exert control of a certain kind over the political or social movements of another nation, there is no formal legal connection established between the two. Rather, in an informal empire, the more powerful of the two countries might offer its military support and protection to the other country (which therefore becomes its protectorate), but it is not directly responsible for the governance and administration of that country. Often, there is some level of threat involved in the balance of power between the countries: the more powerful country may offer its protection only on the condition that a political party of which it approves remains in government, or on the condition that the protectorate refrains from engaging in trade or other alliances with certain other countries. Because of the threat of having the protection taken away, the protected country will conduct itself, to a considerable extent, in line with the interests of the larger power.
Informal imperialism often involves spreading the political ideology of the more powerful country through the use of education and religion. Trade agreements may be established which are generally unfavorable to the subordinate country, whose natural resources the more powerful country may want. However, there is no direct government control or military occupation of the colony or protectorate, as there would be in a formal empire situation.
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