In his new book "The Shadow War," CNN's Chief National Security correspondent Jim Sciutto explores China and Russia's secret war against the U.S.-led international order. Though readable and well-sourced, the book isn't comfortable reading.

Because it makes clear that America's top adversaries are winning silent but very significant victories.

"The pace and power of the Shadow War can be frightening," Sciutto writes.

Sciutto's first point is that we still haven't sufficiently recognized the nature of the threat. He charts the delusion by which successive U.S. administrations have viewed China and Russia as states interested in compromising under the U.S.-led order. Sciutto shows how this delusion has allowed these top adversaries to fight us while telling us what we want to hear.

The shadow war, then, is one fought in the political margins between peace and war, and tactical arena between covert action and overt force. Charting a course around the world, "The Shadow War" takes us inside the war's various theaters.

We see how Estonia responded to a dramatic Russian cyberattack with a societal mobilization to do better next time. "Cyber-hygiene, cyber-hygiene , and cyber-hygiene," President Kaljulaid tells Sciutto, "We teach our people, it's essential."

We see how China engages in an industrial-level theft of U.S. intellectual and military secrets. Seeing the scale of what China is doing, the courageous FBI effort to counter these threats seems like a losing battle. But this book is also informed by Sciutto's former service as chief of staff at the U.S. Embassy in Beijing from 2011-2013. The author explains how this service was instructive. He learned, for example, that, "U.S. firms — though aware of the theft — often refused to ask for [U.S.] government help, or to identify cyber-breaches, for fear of alienating their Chinese partners or losing access to the Chinese market altogether." Sciutto points out that "China's strategy relies on — and cultivates — that fear."

Yet, while he served during the Obama administration, Sciutto isn't biased. The CNN anchor offers particular criticism of the Obama administration's response to Russia's 2014 incursion into Ukraine, and its handling of Chinese militarization efforts in the South China Sea. Sciutto also rightly criticizes President Obama's reliance on personal pledges made by President Xi Jinping.

Heading to the U.S. Military's Strategic Command, "thirty feet underground, in perhaps the world's most powerful command and control center," we see alarming detail on the impressive developments China and Russia have made in satellite weapons. We're left in no doubt here as to the stakes. If a space war takes place, the debris that might follow could end space exploration as we know it. Still, Sciutto offers some hope that evolving U.S. capabilities might rebuild some balance of power.

The book is fortified by its accessible writing. Visiting U.S. Navy personnel in the freezing Arctic, Sciutto offers a metaphor for how American responses to the shadow war require uncomfortable places and ideas: "I was wearing multiple layers of military-grade-polar gear, but the cold attacked my extremities quickly. I imagined the first explorers trudging through here in leather and fur and marveled at the combination of toughness and ambition that kept them going."

In this resolution we learn that "The Shadow War" isn't just a reporting book. It's a guidebook. Each chapter concludes with Sciutto's narrowly drawn lessons about how American policymakers might better contest our adversaries. There's a flowing patriotism in Sciutto's desire to see the U.S. government act more effectively.

Nor does the author shy away from the fact that winning won't always be cheap: He observes that "meeting the challenge also requires new investments and advancements in next-generation weapons systems, such as hypersonic weapons ... investing in old warships, perhaps including even the revered aircraft carrier, is not sufficient to maintain the U.S. advantage."

There are regular identifications as to why this all matters. In one lesson, Sciutto notes that "China's construction of man-made islands [in the South China Sea] is an expansive and imminently tangible challenge to the rules-based international order established and championed by the United States since the end of World War II."

The stakes are great, and Sciutto wants America to win. His book is necessary reading for those who share that sentiment.

Published by Harper Collins, "The Shadow War" will be released on May 14.