On Friday’s “NewsHour” on PBS, New York Times columnist David Brooks poked holes in all of the possible justifications the Obama administration has for opposing the construction of Keystone XL pipeline.

The issue has been re-raised in recent days as Sen. Mary Landrieu (D-LA) and her opponent, Rep. Bill Cassidy (R-LA), vie to win political favor in their upcoming runoff contest next month for the U.S. Senate seat currently occupied by Landrieu.

Partial transcript as follows:

HARI SREENIVASAN, anchor “PBS Newshour”: OK. Shifting gears about energy, let’s talk about the Keystone XL pipeline. The House voted on it today. It’s likely to get to the Senate floor, at least on Tuesday. Is this purely political? I mean, it was motivated in part by the race that is happening in Louisiana with Mary Landrieu and her competitor.

BROOKS: Yes. Well, it’s purely political in the timing. There’s nothing wrong with politics. It’s interest people — interest groups trying to get their interests advanced.

And so the timing is political. I happen to think the president’s opposition is purely political. There is a big State Department series of reports, gigantic reports on the effect of the Keystone pipeline. They found, economically, it would create thousands of jobs, not huge amounts of job, but thousands of jobs. The economic damage, they found, would be none.

The greenhouse gas emissions  — that oil is going to be pumped or not pumped depending on the price of crude, not depending on whether we have a pipeline. It’s either going to be pumped and sent through hundreds of thousands of train cars or be sent in a more environmentally friendly way under the ground.

And so the environmental rationale for the pipeline seems to be strong. The economic rationale is not huge, but it’s significant. And so if you follow the science, if you follow the research, the case for the pipeline is overwhelming. The president is not doing it to secure his left base, because it’s a good a fund-raising tool for a lot of people. Not for very good reasons.

SREENIVASAN: OK. Mark?

MARK SHIELDS, Creators Syndicate columnist: This has to be the most thoroughly researched, meticulously studied idea, this pipeline, in the history of humankind.

It’s been slow-walked to the point of a standstill. And now it’s going to come to a vote finally in the Senate because Mary Landrieu, who is in a runoff for her Senate seat and an underdog in Louisiana December 6, has pushed it and is going to demonstrate her own independence from the White House and her clout or leadership or however you want to put it.

And the senators who want to vote against it will get a chance to vote against it. And people who want to vote for it will vote for it. And I think the president will veto it. And I think that will be the end of it, other than it won’t be built, and it will not be a major issue in the 2016 campaign.

But I do think that the argument basically politically is on the side of those who want to build it.

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