Breathless coverage of the revelations that the National Security Agency (NSA) has been tracking allied foreign leaders aside, spying on allies -- even friendly ones -- is nothing new in international politics. In the mid-sixteenth century, the pious King Philip II of Spain and the pope kept tabs on each other as they prepared for the sailing of the Spanish Armada against Britain. The reason? The pope thought the king indecisive, and the king believed that the pope was hedging his bets.
Centuries later, in early 1917, the British government wanted the United States, then neutral, to enter World War I on its side. According to Keith Jeffery, the official historian of MI6, London’s intelligence service, the British used a “whole range” of overt and clandestine methods to gather intelligence and run influence operations. For example, thanks to its secret surveillance of a U.S. transatlantic cable, MI6 learned of a German plot to win Mexico’s allegiance by promising the country a chunk of U.S. territory. Masking its source, MI6 delivered the alarming news to U.S. President Woodrow Wilson and thus nudged the United States toward a declaration of war.
Signal intercepts were not the United Kingdom’s only source of intelligence on its hoped-for ally: Sir William Wiseman, a British intelligence operative, penetrated the White House by earning the trust of Wilson and his closest adviser, Colonel Edward House. While also running illegal covert operations on U.S. soil, Wiseman gathered intelligence on Washington’s opinions about the conduct of the war, its preferences for how some postwar territorial issues would be resolved, and its strategy for the Paris Peace Conference.
The United States returned the favor by collecting the communications of friendly powers during the peace negotiations. Even as Wilson publicly espoused open diplomacy, his closest advisers had hired the cryptologist Herbert Yardley to run a signal and cipher unit that gathered intelligence on the other delegations. Yardley provided a similar service at the Washington Naval Conference, during which, thanks to his work, the United States was able to win major limitations on the presence of foreign navies in the Pacific. Shocked to learn of Yardley’s activities, U.S. Secretary of State Henry Stimson shut down his “Black Chamber” in 1929, declaring that “gentlemen do not read each other’s mail.” But Stimson changed his mind soon thereafter, advocating the creation of a successor, the NSA, after World War II.
Friends don’t just tap friends’ phones and read their mail. In one particularly notorious case, the Israeli government bought sensitive intelligence from a U.S. analyst, Jonathan Pollard, who received a life sentence for espionage in 1987. Despite appeals from the highest levels in Tel Aviv, Pollard remains in a North Carolina prison. Meanwhile, in 2003, the United States was caught spying in Italy because it wanted to render a terrorist out of the country. The Italians were not amused and, in 2009, convicted the American station chief and 22 others. To catch the operatives, Italian law enforcement had monitored the cell phones of a friendly intelligence service.
That everyone does it is, of course, no excuse for intelligence run amok, as insiders argue was the case in the Pollard espionage. The Israeli government recruited and rewarded Pollard for collecting intelligence on Arab militaries, but it apparently accepted his intelligence on U.S. sources and methods as well. The overreach was hardly in Israel’s interests given the risks to its larger relationship with the United States.
There are, however, plenty of good reasons for allies to spy on each other: to protect interests that an ally disregards, to guard against double-dealing or betrayal, to protect against allied vulnerabilities, to guard against surprise stemming from diverging interests, and to protect against a good “friend” simply getting things wrong. Wiseman’s role in the run-up to the United States joining World War I, a role that was reprised by William Stephenson in the lead-up to World War II, could be put in that last category. Although U.S. interests lay with the United Kingdom in both cases, U.S. entry into the wars was uncertain. London’s mission was to learn American thinking and nudge Washington along.
One of these legitimate categories concerns the disregard of an ally’s interests. For example, U.S. soldiers sometimes go to war against states equipped with highly advanced weapons sold to them by third parties, including allies. Understanding how to defend against these weapons may require information on how they work. Although it is unconscionable for governments to gather such proprietary information from foreign firms for competitive advantage, doing so to protect soldiers’ lives and win wars may be necessary if an allied government refuses to hand the data over or make its industry divulge it. Allies deny such intelligence to each other because, although politically friendly, they are still economic competitors; their counterintelligence services are, as a result, often at war with each other.