The influence of ideology in political, economic and legal systems may take the form of pressure from organized religion or nontheistic needs. Ideological influence exerted by pressure groups may lead to international conflict and war, to civil war, guerrilla war and subversive activities. Internally it may lead to repression, militarism, conformity and denial of democracy. Many ideologies are not brought completely into open, public debate and work underground, buying influence and moving into strategic positions.
The two main vehicles of ideological influence are the spoken word (that is, the rhetoric of politics) and the written word (that is, the power of the press). Of the two, the press is much more influential and for that reason, dangerous, when it is the tool of an ideology that leads it to suppress, distort, or otherwise report in a biased way. The ideological influence of the press is incalculable, and by extension, television journalism and book publishing as well.
A free press does not guarantee freedom from ideological influence, as the media may be polarized or fragmented with bias in every direction from pressures of owners, advertisers or the community served. On the other hand, the closing of newspapers by government decree, or the prohibition on publishing or distributing certain books, are the acts of a tyrannic ideology that is embraced by government.