When subjects like soft power and public diplomacy are discussed in forums like this, few people have postage stamps in mind, but there has long been a close connection between philately and foreign policy.

In themselves, stamps express sovereignty, but they are also examples of political iconography and visual indicators of official attitudes and policies, aimed at both domestic and international audiences.

The use of stamps as projections of national identity can be traced back to their origin in 1840, when stamps carrying portraits of Queen Victoria began to be used throughout the British Empire. Even before the Universal Postal Union was formed in 1874 to permit the free flow of international mail, stamps were used to mark a country's independence, stake territorial claims, record military victories, honour statesmen and support multilateral institutions.

There are now about 600 stamp-issuing entities, or 'authorities', around the world. Over the last century and a half they have produced an estimated 250,000 different designs. Through the use of unique and often striking visual statements in a small two dimensional space, they have covered themes as far ranging as nationalism, history, politics, economics, art, cultural identity and foreign relations.

Authoritarian governments in particular have been quick to recognise the propaganda value of stamps, and to use them in international campaigns. During the Cold War, for example, the Soviet Union used stamps to trumpet the glories of communism. North Korea is still one of the most prolific issuers of stamps portraying icons of its own and other revolutionary movements. Cuba's stamps also display a stubborn attachment to such themes.

These days, China has become particularly adept at promoting its relations with other countries through the issue of commemorative stamps, usually celebrating the establishment of diplomatic ties and other major events. Some joint issues have been paid for entirely by Beijing. Not only do such stamps promote China as a friendly global power, but they help strengthen its ties with strategically important states.

It is also possible, through the study of a country's postage stamps, to see the historical development of its foreign relations.

Afghanistan's stamp issues between 1948 and 1992, for example, mark the 1973 coup that toppled the monarchy, the 1978 Marxist revolution that overthrew the republic, the Soviet invasion in 1979, the withdrawal of troops in 1989 and the short-lived government that collapsed in 1992.

In Burma's case, successive governments have been quite conservative in their use of postage stamps as diplomatic tools. Issues have been used almost exclusively to promote official programs and mark major events, within and outside the country. From independence in 1948 to the 1988 pro-democracy uprising, about 37% of stamp issues emphasised broad nationalist themes, while 18% were on revolutionary and military subjects. 

During this period, the U Nu and Ne Win governments pursued strictly neutral foreign policies. A few countries commemorated state visits to and from Burma on their postage stamps but no bilateral relationships were recognised on Burmese issues. Rather, emphasis was given to multilateral institutions and international events. Between 1948 and 1988, some 40% of Burma's stamps were dedicated to UN-related themes.

After a new military government took over in 1988, however, there were a number of significant changes to this policy.

Over the past 25 years, UN-related themes have almost disappeared from Burmese stamps, probably reflecting the deterioration of relations since the UN began to criticise Burma for its human rights abuses. Emphasis has been given instead to the achievements of the military regime and political milestones, such as the inauguration of a new government in 2011. At the same time, attention has been paid to Burma's evolving foreign relations.

Burma issued a stamp to mark the 30th anniversary of ASEAN in 1997, the year it joined the Association. In 2007, Burma collaborated with other member states to produce a mini-sheet commemorating ASEAN's 40th anniversary, and in 2012 it issued a set of stamps to mark the 11th ASEAN Telecommunications Senior Officials Meeting in Naypyidaw. It is expected that Burma will issue a new stamp this year when it assumes the ASEAN chair.

In a notable break with past practice, Burma and China jointly issued a stamp in 2000 to mark the 50th anniversary of the establishment of diplomatic ties. This was followed in 2010 by a stamp to celebrate the 60th anniversary. In 2013, there was another joint issue, this time with Russia, to mark the 65th anniversary of diplomatic relations between Burma and that country. No other states have been recognised by Naypyidaw in this fashion.

Unlike most other countries, Burma has eschewed portraits of prominent individuals. Independence hero Aung San was an occasional exception before 1988, but even his face disappeared from stamps (and the national currency), since his daughter began to challenge the military regime. It has been suggested that this was in part because Aung San Suu Kyi bore a striking resemblance to her father.

Indeed, when Aung San Suu Kyi's portrait was included in a set of eight stamps issued by Norway in 2001, to mark the centenary of the Nobel Peace Prize, the stamps were banned in Burma. The country's opposition leader has appeared on the stamps of several other countries, and on unofficial issues produced to mark special events, such as her receipt of the Sakharov Prize last year.

Another Burmese figure who has been portrayed on foreign postage stamps is former UN Secretary General U Thant. He has been honoured in this way by more than a dozen countries, but not Burma, largely because Ne Win resented the global standing of U Nu's former secretary. In 2009, the UN Postal Administration issued three stamps to commemorate the 100th anniversary of U Thant's birth.

The only time a senior Burmese military figure has been portrayed on a postage stamp was in 2000, when a picture of Senior General Than Shwe (then Chairman of the State Peace and Development Council) was included in the world's largest mini-sheet, issued by Liberia. It depicted the heads of state of all 190 UN members.

Some attention is now being paid to postage stamps by academic researchers, but they remain a neglected source. They are easily dismissed as colourful curiosities, or ephemera unrelated to affairs of state. However, they can provide a window onto the domestic and international politics of countries. Stamps are emblematic devices that illustrate how the issuing states wish to be seen, not only by their own citizens but also by those beyond their borders.

It is possible that in this era of emails, Skype and social media, the heyday of the postage stamp is over, but they are still important. This is particularly so in countries like Burma, where electronic communications are under-developed. In any case, given the dearth of reliable information about Burma's domestic politics and foreign relations, no source should be seen as unworthy of serious consideration.

Image courtesy of the Burma Philatelic Blog.