A congressional conference committee this week started trying to reconcile radically different provisions of two different transportation bills passed by the U.S. Senate and the House of Representatives.

Passing a viable transportation bill is crucially important for the still-sluggish American economy. Usually, except for fighting over who gets what share of the public works money, political parties cooperate on such bills. They authorize highways, bridges and public transit systems, among other things, projects that create jobs and improved infrastructure that benefits consumers and businesses alike.

But this year the House chose a silly approach: a three-month extension of current authorizations larded down with election-year ideology and nonsense. The Senate’s more serious two-year bill keeps the focus on current and future transportation needs. What a concept.

The silliest House provision would grant approval to a Canadian company’s controversial application to add about 1,600 miles to an existing 2,100-mile oil pipeline system. TransCanada’s Keystone pipeline already runs from northern Alberta to Cushing, Okla., with a spur running across Missouri to refinery and storage facilities at Roxana and Patoka, Ill.

The new Keystone XL proposal adds another pipeline along a different route from Canada to Cushing and then on to Texas refineries.

The Keystone XL proposal is a hustle being sold on phony promises of tens of thousands of jobs and environmental safety. This latest Republican-led attempt (with the support of some Democrats and labor unions) to bypass procedural safeguards and force the proposal down America’s throat is no more acceptable than the previous failed attempt in January.

TransCanada, a private, foreign company, also continues to use the power of eminent domain to pressure U.S. landowners to grant easements for the pipeline and, in some cases, to seize property in court. The transportation conference committee must make sure the final version of the bill is free from any Keystone XL contamination.