The Globe and Mail reports in its Wednesday edition that U.S. President Donald Trump's belligerence over Greenland and a massive sell-off in Japanese government bonds shattered global market calm on Tuesday, sending stock markets sharply lower. The Globe's Andrew Galbraith and Mark Rendell write that this geopolitical uncertainty mixed with investor concern about the sustainability of Japanese government debt caused Japanese bond yields to soar on Monday and Tuesday, rippling out through global markets. "It's hard to disentangle how much of this was Japan, how much of this was worries over Greenland," Gennadiy Goldberg, TD's head of U.S. rates strategy, told The Globe. "I would suspect more over Japan. But as the day progressed, and as the Greenland tensions continue to escalate, this could create additional fears that another wave of foreign selling [of U.S. government bonds] could be coming." He added: "I think the big fear is foreign investors no longer buying Treasuries. And given that about a third of the U.S. Treasury debt is owned by foreign investors, that's a particularly important source of demand." Danish pension fund AkademikerPension said Tuesday that it would sell its U.S. Treasury holdings.