John U Bacon tells the story of the Great Halifax Explosion of WWI.  The Halifax Explosion was a maritime disaster in Halifax, Nova Scotia, Canada, which happened on the morning of 6 December 1917. The Norwegian vessel SS Imo collided with SS Mont-Blanc, a French cargo ship laden with high explosives, in the Narrows, a strait connecting the upper Halifax Harbour to Bedford Basin. Thousands were killed or wounded in seconds.  The people of Boston rose to the challenge sending medical supplies, doctors, nurses and money.  These spontaneous actions changed the relationship between the USA and Canada forever.