John J. Tkacik On Taiwan: “First Island Chain” means “Taiwan”

The news from General Christopher C. LaNeve, Vice Chief of Staff of the US Army, last month was a low-key 46 pages, but one sentence was arresting: the US Army will “organize, train, and equip against the People’s Liberation Army (PLA) — the ‘pacing threat’ — with the same institutional focus that the Cold War generations brought to the Soviet Army.” Ouch!

The sentence was in an unclassified document entitled “How The Army Fights,” and billed as “Operational Warfighting Guidance” for the Army; it is comprehensive and “multi-domain”; it covers the globe. Despite its breadth, there was no mistaking its focus on the Pacific, and particularly the “First Island Chain” (subtly called the “FIC”). Let me offer some history on the “FIC” concept and also share a thought on the “SIC” (the “second” one, which also unsettles me).

The “FIC” means “Taiwan.” The FIC is meaningless without Taiwan. I learned this 45 years ago from a somewhat flippant aside: “Keep Island Asia out of the hands of Mainland Asia. That’s been America’s strategy since MacArthur.”

Those were words the late William W. “Bill” Thomas put in a letter to my boss, Donald Ferguson, in 1981. Bill was then deputy director of the American Institute in Taiwan (AIT) and Don was chief of Taiwan Coordination in the State Department. Bill was responding to a back-channel telegram from Charles W. “Chas” Freeman in Beijing expressing the embassy’s dissatisfaction with our out-of-date “policy” on Taiwan.

At the time, I mistook Bill’s epigram for a general comment on “Asia vs. Pacific,” “Mainland Asia” vs. “Island Asia.” But I soon grasped that Bill’s “Island Asia” was MacArthur’s “Island Chain,” and that the term “Island Chain,” in China policy argot, had been a synecdoche for “Taiwan” since at least April 1951. Indeed, the “Island Chain” as a strategic concept is incomprehensible without Formosa and China.

In a top-secret June 14, 1950, “Memorandum on Formosa” to the Joint Chiefs of Staff (written presciently 10 days before North Korea’s surprise invasion of the South), the supreme commander in Tokyo, General of the Army Douglas MacArthur, wrote: “I have been concerned as to the future status of Formosa and I have been convinced that the strategic interests of the United States will be in serious jeopardy if Formosa is allowed to be dominated by a power hostile to the United States.” It was the latest of several such memos he had sent to the Pentagon and the Department of State warning of the “strategic consequences which would result from the capture of Formosa by the Chinese Communists.” Formosa was, he said, an “integral part” of those “littoral islands” that formed America’s “western strategic frontier.” Its loss would give Communist China and the Soviet Union an “unsinkable aircraft carrier and submarine tender” equivalent to “ten or twenty aircraft carriers” from which they could menace the Philippines and beyond, both by air and under the sea, just as Japan had done in 1941.

MacArthur was well aware that the State Department hoped the US could seduce Communist China away from its new military alliance with the Soviet Union by allowing Mao Zedong’s (毛澤東) forces to occupy Taiwan in the summer of 1950. Secretary of State Dean Acheson was certain that, in contrast to the USSR’s continued occupation of Outer Mongolia, Manchuria and Xinjiang, America’s acquiescence in a Chinese communist takeover of Taiwan would both improve Washington’s relations with Peking and undermine Moscow’s.

MacArthur was dismissive of such appeasement. Formosa’s fate, he said, “largely rests with the United States” … and “unless the United States’ political-military strategic position in the Far East is to be abandoned,” it was obvious that “a line must be drawn beyond which Communist expansion will be stopped.”

It just so happened that the very day the Korean War erupted, June 24, 1950, the JCS chairman, General Bradley, had hand-carried the highly secret memo from Tokyo and delivered it into the hands of then US President Truman. At an emergency National Security Council meeting on June 25 to set US strategy in Korea, MacArthur and Formosa were first on the agenda. Acheson, a foe of MacArthur’s, suggested that “the future status of Formosa might be determined by the UN,” only to be interrupted by Truman, “or by the Japanese Peace Treaty.” General Bradley echoed MacArthur: “We must draw the line somewhere.” The president agreed and Taiwan was saved.

But 10 months later, on April 11, 1951, MacArthur had been fired (ironically, for his stance on Formosa’s possible contribution in the Korean War, a stance far beyond the president’s tolerance). The following week, after an exhausting air voyage from Tokyo, the fired MacArthur arrived at Washington National Airport. Rather than hail a taxi, he and the Mrs. opted for a twenty-car motorcade (with an escort of three dozen police motorcycles) to the Capitol, where he delivered his farewell speech to a Joint Session of Congress. At the center of his address was the “FIC” and Taiwan.

“We control [the Americas and the Pacific] to the shores of Asia by a chain of islands extending in an arc from the Aleutians to the Mariannas held by us and our free allies.” Yet “holding this littoral defense line in the western Pacific is entirely dependent upon holding all segments thereof, for any major breach of that line by an unfriendly power would render vulnerable to determined attack every other major segment … For that reason, I have strongly recommended in the past as a matter of military urgency that under no circumstances must Formosa fall under Communist control.” Moreover, his views “were fully shared by practically every military leader… including our own Joint Chiefs of Staff.” After his address, General MacArthur quietly recommenced his motorcade from the Capitol and processed two miles down Constitution Avenue (lined by a modest assemblage of 300,000 flag-waving well-wishers) to Constitution Hall, where he was greeted by Generals of the Army George C. Marshall and Omar Bradley, respectively Secretary of Defense and Chairman of the Joint Chiefs.

Now, how is all this relevant to General LaNeve’s “How the Army Fights” doctrine of October 2026?

To begin with, Taiwan is still the unnamed FIC silent partner it always has been. The document is chock-full of Taiwan scenarios; one is mooted in the doctrine’s six “Strike” models (along with Ukraine 2025, Gaza 2025, Ukraine 2026, “Nuclear Battlefield” and a nuclear strike on Guam). The doctrine envisages “high-intensity” battle in the “Luzon Strait” and “close battle” over sustained periods in “North Luzon & Batanes Strait, 2027 — Contested Sustainment in the FIC” — none of which include the South China Sea, and all of which require large cached pre-placements of war materiel in hundreds of dispersed locations — presumably in the Philippines and Japan, but perhaps in other unnamed places. Continuous news media commentary over the past seven years has been frank about the strategic challenges of fighting the PLA in the western Pacific. As US President Donald Trump put it, “You know, we’re supposed to travel 9,500 miles [15,289km] to fight a war. I’m not looking for that. I want them to cool down. I want China to cool down.” Meanwhile, the Pentagon reportedly will dispatch representatives from the Office of the Under Secretary of Defense for Policy, without oversight by AIT, directly to Taiwan’s Ministry of National Defense.

Finally, LaNeve’s “Guidance” posits a most sobering thought: the US homeland is no longer out of reach. In a multi-domain war with China, not only does he presume Guam will be a target of nuclear strikes, but he also presumes America’s infrastructure will come under immediate attack. Cyber and space attacks will be coupled with arson, sabotage, social disorder, disinformation and cognitive warfare of almost unimaginable dimensions. LaNeve posits that US Army deployments in the FIC will not force “escalatory decisions” but, as Tom Lehrer says, “once the rockets are up,” all bets are off. LaNeve’s guidance departs from other Pentagon documents issued over the past 12 months (last November’s National Security Strategy, last Christmas Eve’s Pentagon report on China’s Military Power, and January’s National Defense Strategy) in its overt contemplation of China as the primary adversary. It is unclassified — it is designed to be perused and analyzed by the PLA.

So, if you see any “English teachers” at the Ministry of National Defense, thank them for their service.

One final thought about the “Second Island Chain” or the “SIC”: The US, in conjunction with Australia, France and New Zealand, is spending ridiculous amounts of money, far more than ever before, on infrastructure such as ports, airports and communications in the Mariana Islands, Palau, the Federated States of Micronesia (FSM) and across the Pacific. I do not think the Defense Department (or War Department) yet appreciates how China has already penetrated these partners and beyond. For example, on the island of Woleai in the FSM, just over 400 miles from Guam, a Chinese state-owned company began work in September 2025 to rebuild a World War II Imperial Japanese air base. They are not building airstrips in the SIC for frequent-flier miles.

LJohn J. Tkacik, Jr. is a retired US foreign service officer who has served in Taipei and Beijing and is now director of the Future Asia Project at the International Assessment and Strategy Center. He is also on the Advisory Board of the Global Taiwan Institute.