The Keystone XL tar sands pipeline is back in full force.

The U.S. House tried for the ninth time Friday to approve the project. It succeeded, though not by enough to override a presidential veto. The Senate’s turn is this week.

Here are 23 stories, from an ebook to primers, that will help you navigate the polarized Keystone debate as it heats up—and all the issues on which it touches: our changing energy fortunes, global climate change, pipeline safety, activism and more.

Keystone and the U.S. Oil Boom

1.) Keystone XL: Bush’s No-Brainer, Obama’s Dilemma (Ebook)

“Keystone and Beyond provides the most definitive account yet of the Keystone XL pipeline saga. It also upends the national debate over the pipeline by tracing its origins to policy decisions made by President George W. Bush and Vice President Dick Cheney in the first months of their administration, and to expectations about energy supply and demand that have turned out to be wrong.”

2.) Need for Keystone XL Erodes as U.S. Oil Floods Gulf Coast

“Conditions have changed so radically that U.S. refiners are now exporting record amounts of fuel to overseas customers, and there’s a parade of tankers delivering Texas oil to refineries on the east coast of Canada. As these and other surprising trends unfold, it’s becoming increasingly clear that the controversial Canadian oil import pipeline, the Keystone XL, is not an urgently needed link.”

3.) With U.S. Awash in Oil, Nat’l Interest Argument for Keystone Weakens

‘A country that 150 years ago served as the cradle of the oil industry, but which for decades seemed to face an irreversible production decline, now finds itself, all of a sudden, at the center of an oil boom.’

4.) Map: Another Major Tar Sands Pipeline Seeking U.S. Permit

“While all eyes are on TransCanada’s Keystone XL pipeline, another Canadian company is quietly building a 5,000-mile network of new and expanded pipelines that would achieve the same goal as the Keystone.”

5.) What the Latest Keystone XL Delay Really Means

“The most important effects of the postponement might not be about politics at all. Rather, the passage of time may well highlight two substantive issues for all to see that will factor significantly into the national interest determination: the pipeline’s significance for America’s oil supply and demand and for the world’s climate conundrum.”

---

Keystone and Climate Change

6.) How to Deconstruct the Difficult Math of Keystone XL’s Carbon Footprint

“It’s more art than science to settle on a single number…Whether the resulting numbers are too high, too low or Goldilocks perfect, however, they all point in a single direction: Keystone XL’s fuel comes with a hefty surfeit of carbon.”

7.) Keystone Decision Seen as Climate Change Test for Obama Abroad

“The pipeline would ‘increase climate risks for us all…The world needs to rapidly reduce the carbon intensity of its energy globally if we are collectively to limit the worst risks of climate change.'”

8.) Scientists: Key Parts of State Dept Keystone Review Are ‘Without Merit’

“This letter is significant not only because the group of luminaries is large and their arguments elaborate, but because they wrote specifically to discredit the justification for the pipeline laid out in the State Department’s March 1 draft environmental impact statement, or EIS.”

9.) Canadian Gov’t Emissions Report Undermines Keystone Pipeline Pitch

“President Obama has said his decision on whether to grant the Keystone pipeline a permit will hinge on the amount of CO2 the project contributes to the atmosphere. And he has urged Canada to do more to rein in its tar sands pollution…The challenge is enormous not just because time is short and the technologies are immature, but also because tar sands extraction has been shifting from strip mining to more carbon-intensive in-situ mining.”

10.) Keystone XL Will Fail Obama’s Climate Test If Plunge in Oil Prices Persists

“Low oil prices mean the Keystone XL fails the Obama administration’s carefully hedged litmus test, set by the president himself when he said in June 2013 the pipeline’s impact on climate change would be the deciding factor in whether to approve the project.“

11.) Reading John Kerry’s Mind on the Keystone Pipeline

“Imagine, if you will, John Kerry’s internal monologue—his soliloquy as the State Department prepares to release its final environmental impact statement (EIS) on the Keystone XL pipeline designed to funnel tar sands crude from Alberta across the U.S. midsection.”

---

The Kochs

12.) Koch Brothers’ Political Activism Protects Their 50-Year Stake in Canadian Heavy Oils

“Koch Industries has touched virtually every aspect of the tar sands industry since the company established a toehold in Canada more than 50 years ago”

13.) Timeline: Koch Brothers’ 50 Years in the Tar Sands

The Koch brothers built their first fortune on the particularly dirty form of oil mined in Alberta’s tar sands, and they remain deeply invested there.

---

What Is Dilbit?

14.) A Dilbit Primer: How It’s Different from Conventional Oil

Bitumen extracted from tar sands has the consistency of peanut butter and must be diluted to flow through pipelines. And that’s just the beginning.

15.) Dilbit in Exxon’s Pegasus May Have Contributed to Pipeline’s Rupture

“One theory is that dilbit made pressure swings inside the pipe larger and more frequent—and thus more harmful over time—because it’s heavier and harder to push through pipe, and because its ingredients can vary more widely than conventional crude oils.”

16.) New Pipeline Safety Regulations Won’t Apply to Keystone XL

“Efforts to beef up oversight of the nation’s oil pipelines are progressing so slowly that it’s unlikely any additional safeguards will be in place before construction begins on thousands of miles of new pipelines, including the proposed Keystone XL.”

17.) Few Oil Pipeline Spills Detected by Much-Touted Technology

“An InsideClimate News examination of 10 years of federal data shows that leak detection systems do not provide as much protection as the public has been led to believe.”

18.) Lessons from the Dilbit Disaster: InsideClimate News Op-Ed in the NY Times

“Now that the industry is aiming to fill almost a quarter of America’s domestic oil needs from western Canadian sources, we need a transparent and informed discussion about dilbit’s risks and benefits, up-to-date laws and regulations, and improved leak detection.”

---

Activism

19.) To Defeat Keystone, Environmental Movement Goes From Beltway to Grassroots

“The main force of opposition is a messy amalgam of disparate grassroots efforts stretching from Maine to Utah that has found common cause in stopping the Canada-to-Texas pipeline and other tar sands projects. Instead of relying mainly on inside-the-Beltway tactics, these activists are taking to the streets in protest, engaging in civil disobedience and public education…”

20.) 150 Major Democratic Donors Urge Obama to Reject Keystone Pipeline

Where money talks louder than science, the letter from the donors won’t go unnoticed, the week before Prime Minister Harper is to visit Washington.

21.) Climate Scientist Sees No Choice but to Risk Arrest at Keystone XL Protests

‘This isn’t about me, this is about the future. Just voting doesn’t seem to be enough in this case. I need to be a citizen also, because this is a democracy after all, isn’t it?’

---

Nebraska: Ground Zero

22.) Keystone XL Primer: Why Nebraska Is Ground Zero in the Pipeline Fight

“The ecologically sensitive Nebraska sandhills have become a flashpoint in the debate over whether the 1,702-mile Keystone XL pipeline should be built to transport tar sands crude oil in Canada across five Midwestern states to Texas.”

23.) Nebraska Supreme Court Holds the Key to Keystone XL’s Future

“If Nebraska’s Supreme Court sides with the pipeline’s opponents, that would most likely mean yet more delay in TransCanada’s five-year quest to build the 800,000-barrel-a-day pipeline. The court’s decision is probably still a couple of months away.”