Most entry level English teachers are unwitting agents of foreign policy. While the strategic class of the ESL world, the government officials and the university professors, design how language planning policy is to be carried out overseas, they pay little regard to the work conditions of the tens of thousands of English teachers who work overseas. In the case of the British Council we can see that they will not even provide job security to its teachers.
To a great extent in overseas situations, most of what is called "teaching English" is actaully public diplomacy. This is the main reason why one does not have to actually be a certified teacher to teach English overseas.
As a pubic diplomacy agent, you are a part of your country's "soft power" forces. Soft power is what the former #2 at the US Defense Department, Joseph Nye, calls "the attractiveness of [a country's] culture, political ideas and policies." Hard power is a country's military and economic might.
With the Iraq War, some teachers have to realize that they are now the representatives of countries that are engaging in an illegal war. In some large exchange programs, such as the JET Programme in Japan, their countries have signed a deal with Japan to send them as public diplomacy agents to explain their foreign policy at an individual level.
Although US foreign policy has changed with regards to pre-emptive strikes on other countries, it has always promoted liberal trade policies such as free-trade and corporate capitalism. Furthermore, the TESOL organization has worked hand-in-hand with the government to promote its liberal foreign policy abroad to the detriment of foreign language teachers themselves. They promote the rights of corporations over the rights of individuals and employees. Yet, they exploit these teachers to create a business environment where English can be used to further the growth of corporations and corporate capitalism abroad.