«Canada's Enemies» by Graeme Mount

In 1898, Spanish spies based in Montreal, Halifax, and Victoria monitored the United States war effort against their homeland, while U.S. counter-intelligence officials watched the Spaniards. Neither the Americans nor the Spaniards sought Canadian permission for these activities.
Britain's enemies (and often America's enemies) have also been Canada's enemies. Without the heroic counter-intelligence of the mysterious Agent X, Irish Americans at the turn of the century might have blasted British Columbia's legislature and the Esquimalt naval base the way they blasted the Welland Canal.
During World War I, counter-intelligence failed to stop German agents who bombed the Windsor-Walkerville area as well as the CPR bridge on the Maine-New Brunswick border. Meanwhile, Canadian security officials ran around in a state of frantic frustration because of German “conspiracies” along the Ontario-New York State border imagined by Sir Courtney bennett, British consul-general in New york City. After the war, American moles in a Latvian post office monitored mail between Canadian Communists and Moscow.
In the thirties, a Finnish-Canadian clergyman spied on Sudbury's Red Finns for the United States consultate inNorth Bay, and Hitler's consuls maintained surveillance of Canadian politicians and German dissidents in Canada. During World War II, Canadian authorities intercepted the mail of envoys from Vichy-France, suspected of spying for Germany, and from Franco's Spain, suspected of spying for Japan.
In the 1960s, the CIA not only observed Cubans in Canada, but also watched the situation in Quebec and used a Canadian diplomat to collect information on North Vietnam.
Some of this history has merged from previously ignored and newly declassified documents from European, American, and Canadian archives. These newly revealed details show that Canada is an interesting place, both for what Canadians do elsewhere and for what foreigners do in Canada. Also, once readers have seen the kinds of activities in which friends engage, they may be less surprised at what enemies have done.