Historians have a term for historical randomness: contingency.

It’s a simple idea. Things aren’t bound to happen. They aren’t preordained. Yet, decades after something has occurred, it’s easy to forget that.

Events take on a hue of inevitability.

Contingency is an underlying theme in Adam Sowards’ new book, “An Open Pit Visible from the Moon: The Wilderness Act and the Fight to Protect Miners Ridge and the Public Interest.”

Sowards, an environmental historian at the University of Idaho, digs deeply into the effort to block the mining of Miners Ridge in the Glacier Peak Wilderness Area. The fight, which started in 1966, defined key parts of the scope and breadth of the Wilderness Act.

“I didn’t realize, for example, that this was the first test of the mining provision for the Wilderness Act,” Sowards said.

The act had been passed in 1964 and, until the Kennecott Copper Corp. proposed an open pit in the Cascades (which the opposition stated would be visible from the moon), a key provision allowing mining even in designated wilderness areas, had never been tested.

But when Kennecott announced plans to mine there, a diverse cast of characters resisted.