It occurs to me that there is an easy solution to the foot-dragging the president is doing on the XL pipeline.
Step 1: Build the pipeline on both sides of the border, right up to the border.
Step 2: Recognize that is is current practice to ship the oil by rail in tanker cars across the border.
Step 3: Park a tanker car straddling the border where the two ends of the pipeline would otherwise meet and connect the pipe to their respective ends of the tank car.
Step 4: Turn on the oil. Besides in 2017 the last chunk of pipe can replace the tank car being used as a splice. Of course we would have to pay the railroad the freight rate for all that oil traveling by rail 50 feet, but that should be cheap by comparison to the hundreds of miles they ship it now.
See? Easy. We Americans can do anything.