• an aggressive person
• a person engaged in fighting or warfare (especially when applied to partisan fighters rather than an army)

Frequently, when atheists speak out against such things as religious intrusion on the affairs of statecraft, or even on defending their own rights, are defined as "militant." This characterisation is not solely applied by religious people; ofttimes the popular press will apply the term "militant atheist" to people such as Sam Harris or Daniel Dennett.

The term "militant" is used, especially by apologists, as both a strawman (atheists are angry) and in an equivocation fallacy (the image brought forth is of a group of armed fighters trying to overthrow the established order).

This characterisation of atheists as militant is not accidental. Atheists themselves see advocating for things such as separation of church and state, or standing up for their own rights under the law, as exercising their rights as anyone else in society might exercise them. Few people in our society would claim a Christian exercising his or her right to pray before eating a meal in a restaurant as a "militant Christian" because that person is very publicly praying. (One might think of the New Testament admonition in Matthew 6:5 "And when thou prayest, thou shalt not be as the hypocrites are: for they love to pray standing in the synagogues and in the corners of the streets, that they may be seen of men. Verily I say unto you, They have their reward" but that is not militancy: It is hypocrisy.)

The word "militant" conjures up images such as armed groups trying to overthrow legitimate governments or cause mayhem and terror, fighting the police or army. "Militant" carries a negative connotation (violence). It is no accident that an apologist selects this term (militant) when describing an atheist who simply stands up for the law in such things as state-mandated prayer in school or placing religious iconography on public property.

What is militancy is when the religious choose to subvert the law to religious ends. These actions can take all sorts of forms, from inserting Christian prayers into school-sponsored sporting events to city council meetings, from putting a creche during Christmas in a city-owned park to politicians or religious leaders claiming their faith uniquely qualifies them to lead a city, state, or nation. In all these cases, all the citizens pay for these things, and their tax money should not in the USA be used to promote one faith over another (or lack of faith).

Like other apologetics, calling an atheist who stands up for his or her and everyone else’s rights "militant" is not meant to convert anyone to Christianity. The objective is to reinforce the idea amongst believers that atheists are somehow different and trying to subvert society (rather than standing up for the rights of all including Christians). It is to keep the faithful in the fold, by identifying a clear "other" who is someone to oppose. As Christianity is based on the idea of persecution, and not many have been fed to lions lately, they need a foil to show their oppression, and atheism is that foil. The "militant" atheist is trying to oppress them. Ultimately, the idea of the "militant atheist" is projection on the part of religious believers.

When an atheist is directly called "militant" by a religious believer, the goal is to get the atheist to go back in the closet. The religious believer does not wish to cede ground or acknowledge atheists have equal rights.

A common meme reads: When you’re accustomed to privilege, equality feels like oppression (attributed to Brian Sims, 2015). Militants are often oppressors, and thus atheists are cast into the role of oppressors. Considering how many churches, mosques, temples, and shrines exist in the USA, we’re doing a poor job on the oppression front.