halifax

Every year, Boston gets a giant, free Christmas tree as a present.

The tree is a gift from the city of Halifax, Nova Scotia, and has been sent every year since the 1970s. It sits in Boston Common and is the city's official Christmas tree.

Bostonians should be super proud of that tree. I mean, it's a handsome tree. Nice branches. Very tall. No galls or loose monkeys or whatever passes as ugly in the world of trees. But the real reason Bostonians should be proud isn't about the tree; it's about why they get the gift in the first place.

This is a story about what makes me really, really like humanity.

Let's go back to 1917 and the site of a terrible tragedy.

In 1917, World War I was in full swing and Halifax was a major refitting station for ships throughout the Atlantic. People, relief supplies, and weapons poured from there and into The Great War.

Despite this huge role, Halifax was peaceful. But on Dec. 6, 1917, two ships collided in the harbor. This wouldn't have been a serious problem except that one of them, the Mont Blanc, caught fire.

The Mont Blanc was carrying more than 2,000 tons of explosives. 20 minutes after the collision, the flames found the munitions.

The resulting explosion was unlike anything the world had ever experienced.

At the time, the Halifax explosion was the largest manmade blast ever. It took the invention of nuclear weapons to top it.

1,600 homes were destroyed, and thousands were killed or injured. Nearly the entire north half of the city was gone. The city of Dartmouth, a local Mi'kmaq settlement, and the black community of Africville were also destroyed.

Civilians, firefighters, police, and soldiers immediately organized a relief effort. They fought fires, freed trapped people, and even commandeered cars to act as emergency ambulances. It was long, exhausting work.

Two days later, a train pulled up and immediately distributed a ton of relief straight into Halifax's arms.

The train was packed with food, water, medical supplies — pretty much everything the city needed. Relief workers jumped out, running into the city to relief the exhausted Halifaxians.

Where had it come from? Boston.

Two days before, someone had managed to get a telegraph to Boston, over 400 miles away. Within hours, they'd organized a relief train, sending it north — through a blizzard! — to get Halifax help.

Boston wasn't the only city to help out, but Halifax remembered that train.

The next year, Boston received a giant tree from Halifax as an epic thank-you note.

Later, in the 1970s, the Nova Scotian government decided to revive the practice, turning it into a tradition. They take the tree very seriously; they even employ a Christmas tree specialist to locate and procure a perfect, wild tree.

Humans can be mean and selfish and weird; it's true. But we also have an undeniable instinct to help each other out.

Whenever there's a crisis, you'll also find people helping — newlyweds helping to feed refugees or even the U.S. sending an aircraft carrier to Haiti after Hurricane Matthew.

So Bostonians should be proud of their tree. It's a big, physical reminder that when we can help each other out, we do.