My answer is yes, to know why just read this article.
The Panama Canal would not have been built where it actually has been but for a Stamp Issue! The Canal was actually to be built by American Engineers in Nicaragua, as per the decision taken by the American Congress. Just at this time, Nicaragua brought out a new stamp issue and the design showed Mount Momotomo, a volcano in eruption. The Pro Panama group at once seized the opportunity and sent one stamp each to the supporters of the Nicaragua Route, pointing out the risk to the canal from the volcano. Congress changed their decision and the State of Panama benefited from the prosperity which the canal brought.