I literally posted a link from the Canadian side as to why XL wasn't needed.
I think that employment IS a consideration when a private entity is looking to engage in a project of this size. Balancing the economic impacts with the environmental risks is important. It's a cornerstone of Roosevelt conservation. Don't protect it all, but don't wreck it all.
TC was the only group that stood to make out on this. Why should the US give up its land, take the risk of environmental damage, AND not benefit in a substantial economic way? This deal isn't in our national interest. Not sure, other than it's some political deal now, why Trump would offer to let them start back up. After all, energy is the largest driver of the trade deficit he keeps whining about and damn near tried to wreck our economy over. Hell, Nashville will see real tourism declines solely based on the fact he's ticked Canadians off enough to not visit.