To build and manage the Panama Canal, the United States pushed through Panama's independence from Colombia and spent more on this construction project than on any other before. To create the Suez Canal, the Egyptian government leased its land to a private French company, which used forced labour to complete the project. Nowadays, the question is, will the Arctic frontier become an ecological preserve or an economic engine, an area of international cooperation or confrontation?
For now, the five nations with Arctic borders - Russia, Norway, Denmark, Canada and the US - have agreed to resolve their territorial disputes diplomatically. Countries have exclusive rights up to 200 nautical miles (370km) from shore. But, if the sea ice continues to melt at its current pace, arguments over control will be irrelevant because ships will be able to simply cross the pole through open waters. However, it's unlikely that regular commercial shipping will take off any time soon. Despite the Arctic's rapid thaw, it's still frozen through the winter, making the navigability seasonal. Even then the journey is icy, difficult and dangerous
Large reserves of oil and natural gas, melting ice and dwindling energy supplies in other regions are spurring the territorial claims of countries in the Arctic. These oil, gas and mineral deposits are estimated by the United States Geological Survey to make up 13 per cent of the world's undiscovered oil and 30 per cent of its natural gas.
When the Northeast Passage thawed in 2008, it became the first year both passages were open simultaneously. With the two waterways clear, a vessel could circumnavigate the North Pole - something that has been impossible for at least 125,000 years.
During the Soviet era, nuclear-powered icebreakers helped millions of tonnes of cargo to ship along this route. Transport plunged after the Soviet Union collapsed. If melting ice reduces the coast, as many scientists project, ships moving between northern Europe and Asia could cut transit time by 10 to 15 days.
Russia's Arctic militarization
Russia is building 10 new search-and-rescue stations at ports along half of the Arctic shoreline. It has also significantly increased its military presence by reopening bases abandoned after the collapse of the Soviet Union. Decades of cooperation in the Arctic Council ended with Moscow's annexation of Crimea in 2014.