What does Donald Trump's shock proposal to buy the island from Denmark tells us about modern-day sovereignty and Arctic geopolitics?

Manuela Saragosa puts the question to two law professors. Joseph Blocher of Duke University explains why the practice of nations buying and selling large tracts of land fell out of favour, and whether it could make a comeback, while Rachael Lorna Johnstone of the University of Akureyri in Iceland says the reaction from the Danish government to Trump's Greenland offer shows how Europeans take the self determination of formally colonised peoples seriously.

Plus Mikaa Mered, professor of Arctic & Antarctic geopolitics at the Ileri School of International Relations in Paris, says the Trump's offer belies his administration's claim not to believe in climate change.

And if you cannot buy another country, why not just carve out your own one? Kevin Baugh is the self-styled President of the Republic of Molossia, a few acres of desert in Nevada and California that has its own customs, passports and national anthem.

(Picture: Old map depicting Greenland and Iceland; Credit: JeanUrsula/Getty Images)