What is espionage and why do governments, companies, and people spend major resources on it?

Perhaps this question was best answered by the hero of the Napoleonic Wars, Arthur Wellesley, the Duke of Wellington, who was “guessing what was at the other side of the hill.” 

The goal of espionage, intelligence, or spying, is usually to find information, especially regarding knowledge (what do you know that we don’t) or intentions (what do you plan to do, and why?).

Intelligence is about understanding an adversary, whether military, business or personal. Governments gather intelligence to become informed about what other countries are planning to do, whether to improve their own negotiating position, or to anticipate what repercussions intended or unintended actions might create. In the private sector, companies seek information about their competitors and their products. Stealing technology is often cheaper and faster than paying for independent research. Investors also perform “due diligence” investigations on companies that want to borrow their money.

In countries like Canada, most intelligence comes from open source intelligence: sources like newspapers, television, or the internet. In fact, most intelligence in the western world derives from publicly available sources.

However, sometimes “what was at the other side of the hill,” or in an enemy’s filing cabinet, or tactics being transmitted to soldiers, all represent secret, highly sensitive information. For this, the goal of espionage – agencies, tools and tactics— is to learn what others try to keep secret.

Since some information is always restricted, adversaries develop plans, operations, and techniques to identify what information they can. Furthermore, those holding that information, aware that adversaries want to steal it, will conceal it and try to deceive others, in order to protect their data. In other words, every action has a reaction, which often leads to further security measures

Espionage has played a continuing role in Canada's early development, long before Canada established formal intelligence agencies, or became a full member of international intelligence sharing partnerships. Canada's present existence results to a considerable extent from the use of espionage.

Consider these examples: James Wolfe used deceptive tactics at the Plains of Abraham in 1759; Isaac Brock had advance knowledge of American intentions at Detroit in 1812; Sir John A. Macdonald ordered pre-Confederation investigations into the United States to uncover possible Fenian invasion plans; and Canada played a role in allied code-breaking during World War II. From our start to our present, Canada's very existence has repeatedly depended on “guessing what was at the other side of the hill.”