For the third time in the past four years, Americans are choking on smoke from Canada’s burning forests. Last week, roughly 900 wildfires turned the skies over Minneapolis, Chicago and New York into an apocalyptic haze. …Why does this keep happening? …Canada isn’t the only one with a wildfire problem. America’s forests are burning too. Fires are raging in northern Minnesota and across much of the western United States. …The media and politicians are quick to blame climate change, but the reality is that forest management works. Fuel treatments such as thinning, brush clearance and prescribed burning remove small trees, brush and dead material that allow flames to climb into the canopy and explode into a dangerous crown fire. …Canada does strikingly little of this work. The problem is that Canada has regulated the cure nearly out of existence. …American forest management is snarled by many of the same problems.