This post has been updated.

On​ ​April​ ​15,​ ​1969,​ ​a​ ​U.S.​ ​Navy​ ​reconnaissance​ ​plane​ ​took​ ​off​ ​in​ ​from​ ​an​ ​airbase​ ​in​ ​Japan​ ​on​ ​a​ ​routine​ ​mission​ ​to​ ​spy​ ​on​ ​an increasingly​ ​belligerent​ ​threat​ ​-​- ​North​ ​Korea.

The​ ​flight​ ​commander​ ​was​ ​nervous.​ ​In January the previous year,​ ​North​ ​Korea​ ​captured​ ​the​ ​USS​ ​Pueblo​ ​spy​ ​ship,​ ​holding​ ​more​ ​than 80​ ​crewmen​ ​hostage​ ​at​ ​a​ ​prison​ ​camp.​ ​Preflight​ ​intelligence​ ​reports​ ​indicated​ ​the​ ​North​ ​Koreans​ ​were​ ​still​ ​agitated ​about the​ ​snooping.

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​The​ ​plane​ ​had​ ​been​ ​flying​ ​over​ ​the​ ​Sea​ ​of​ ​Japan​ ​for​ ​about​ ​five​ ​hours​ ​when​ ​two​ ​North​ ​Korean​ ​MiGs​ ​pounced,​ ​firing​ ​a missile that​ ​killed​ ​all​ ​31​ ​crew​ ​members.​ ​

Nearly​ ​50​ ​years​ ​later,​ ​the​ ​incident​ ​– and President Richard M. Nixon’s choice not to retaliate — has​ ​been​ ​mostly​ ​forgotten. But on Tuesday, during a major speech in South Korea, President Trump brought up the attack. Any sort of provocation, Trump said, would be met with force.

“We have learned together,” he said, “the high cost of weakness.”

And he issued a warning: “Do not underestimate us. Do not try us.”

In recent months,​ ​with​ ​North​ ​Korea​ ​girding​ ​for​ ​war​ ​–​ ​conducting​ ​frequent missile​ ​tests,​ ​threatening​ ​to​ ​shoot​ ​down​ ​U.S.​ ​planes,​ ​trading​ ​insults​ ​with​ ​President​ ​Trump​ ​–​ ​historians​ ​and​ ​national​ ​security analysts​ ​have been ​reexamining​ ​the​ ​1969​ ​attack,​ ​particularly​ ​declassified​ ​documents​ ​that​ ​reveal​ ​Nixon’s​ ​struggle to​ ​retaliate​ ​amid ​​the​ ​Vietnam​ ​War.​ ​

Short​ ​of​ ​all-out​ ​destruction​ ​of​ ​North​ ​Korea,​ ​Nixon’s​ ​national​ ​security​ ​team​ ​couldn’t​ ​promise​ ​that​ ​even​ ​targeted​ ​airstrikes wouldn’t​ ​escalate​ ​the​ ​conflict,​ ​leading​ ​to​ ​untold​ ​deaths​ ​in​ ​South​ ​Korea​ ​and​ ​a​ ​wider​ ​conflict​ ​in​ ​the​ ​region, perhaps​ ​drawing in​ ​China​ ​and​ ​Russia.

“I​ ​think​ ​it’s​ ​a​ ​problem​ ​that’s​ ​still​ ​present​ ​today,”​ ​said​ ​Robert​ ​A.​ ​Wampler,​ ​a​ ​senior​ ​fellow​ ​at​ ​the​ ​National​ ​Security​ ​Archive, a​ ​George Washington University think​ ​tank​ ​that​ ​successfully​ ​pushed​ ​for​ ​release​ ​of​ ​documents​ ​related​ ​to​ ​the​ ​incident.​ ​”What​ ​can​ ​you​ ​do​ ​to​ ​ensure​ ​that​ ​nothing else​ ​will​ ​happen?”

From​ ​Truman​ ​to​ ​Trump,​ ​North​ ​Korea​ ​has​ ​vexed​ ​13​ ​presidents​ ​–​ ​during​ ​the​ ​bloody​ ​Korean​ ​War,​ ​which​ ​claimed​ ​the​ ​lives​ ​of​ more than​ ​33,000​ ​U.S.​ ​military​ ​service​ ​members;​ ​in​ ​1976,​ ​when​ ​North​ ​Korea​ ​attacked​ ​and​ ​killed​ ​several​ ​American​ ​soldiers​ ​with​ ​axes in​ ​the​ ​demilitarized​ ​zone;​ ​in​ ​1994,​ ​when​ ​a​ ​U.S.​ ​military​ ​helicopter​ ​was​ ​shot​ ​down,​ ​leaving​ ​the​ ​co-pilot​ ​dead;​ ​in​ ​2009,​ ​when North​ ​Korea​ ​sank​ ​a​ ​South​ ​Korean​ ​warship,​ ​killing​ ​46​ ​crew​ ​members.​ ​

Only​ ​now,​ ​there’s​ ​a​ ​new​ ​wrinkle:​ ​nuclear​ ​missiles.​​ ​

Just last week, the Pentagon warned lawmakers that a ground invasion would be required to secure all of North Korea’s nuclear weapons sites and that U.S. forces could face biological and chemical weapons.

A​ ​pre-emptive​ ​U.S.​ ​military​ ​strike​ ​on​ ​North​ ​Korea​ ​would​ ​trigger​ ​”a​ ​large-scale​ ​peninsular​ ​and​ ​regional​ ​conflict,​ ​involving hundreds​ ​of​ ​thousands​ ​of​ ​troops​ ​and​ ​potentially​ ​hundreds​ ​of​ ​thousands​ ​of​ ​civilian​ ​casualties,”​ ​a​ ​recent​ ​Brookings Institution report​ ​concluded.​ ​​

Both​ ​sides​ ​are​ ​amping​ ​up​ ​the​ ​rhetoric.

In recent months, he has​ ​taken​ ​to​ ​calling​ ​North​ ​Korean​ ​leader​ ​Kim Jong​ ​Un “Little​ ​Rocket​ ​Man.”​ ​Kim,​ ​in​ ​return,​ ​has​ ​called​ ​Trump​ ​a​ ​”mentally​ ​deranged​ ​U.S.​ ​dotard.”​ ​

Beyond​ ​the​ ​name​ ​calling,​ ​the leaders​ ​have​ ​each​ ​threatened​ ​horrific​ ​destruction​​upon​ ​the​ ​other,​ ​with​ ​Trump​ ​promising​ ​”fire​ ​and​ ​fury.”

To​ ​the​ ​families​ ​who​ ​lost​ ​relatives​ ​that​ ​day​ ​in​ ​1969,​ ​the​ ​verbal​ ​missiles​ ​have​ ​been​ ​a​ ​traumatic​ ​flashback​ ​to​ ​the​ ​very​ ​real rocket​ ​North​ ​Korea​ ​fired​ ​at​ ​the​ ​Navy​ ​plane.​ ​Many​ ​belong​ ​to​ ​a​ ​Facebook​ ​group,​ ​sharing​ ​old​ ​photos​ ​and​ ​memories​ ​–​ ​and,​ ​lately, their​ ​views​ ​on​ ​the​ ​conflict.

“Someone​ ​just​ ​needs​ ​to​ ​be​ ​silent​ ​(president),”​ ​one​ ​member​ ​wrote,​ ​”and​ ​surprise​ ​the​ ​crap​ ​out​ ​of​ ​them​ ​like​ ​they​ ​did”​ to​ ​the downed​ ​spy​ ​plane.

Joe​ ​Ribar,​ ​a​ ​Texas​ ​police​ ​officer,​ ​was​ just three months old​ ​when​ ​his​ ​father,​ ​Lt.​ ​Joseph​ ​R.​ ​Ribar,​ ​was​ ​killed.​ ​His​ ​body​ ​and another were​ ​the​ ​only​ ​ones​ ​recovered​ ​in​ ​the​ ​rough​ ​waters​ ​of​ ​the​ ​Sea​ ​of​ ​Japan.​ ​

Ribar​ ​has​ ​a​ ​hunch​ ​about​ ​where​ ​the​ ​tensions​ ​are​ ​headed.

“I’m​ ​fully​ ​expecting,”​ ​he​ ​said,​ ​”another​ ​plane​ ​to​ ​be​ ​shot​ ​down​ ​out​ ​there.”

‘Vehement and vicious language’

The​ ​plane​ ​North​ ​Korea​ ​shot​ ​down​ ​was​ ​an​ ​EC-121​ ​–​ ​hulking​ ​and​ ​armed​ ​only​ ​with​ ​high-tech​ ​surveillance​ ​gear​ ​that​ ​monitored​ ​sensitive communications​ ​in​ ​the​ ​region,​ ​including​ ​in​ ​Vietnam.

Lt.​ ​Cdr.​ ​James​ ​H.​ ​Overstreet​ ​led​ ​the​ ​operation,​ ​code​ ​named​ ​”Deep​ ​Sea​ ​129.”​ ​He’d​ ​been​ ​on​ ​dangerous​ ​missions​ ​before,​ ​including harrowing​ ​flights​ ​in​ ​Vietnam.​ ​But​ ​something​ ​about​ ​this​ ​flight,​ ​over​ ​less​ ​dangerous​ ​international​ ​waters,​ ​made​ ​the​ ​34-year-old pilot​ ​from​ ​Mississippi​ ​anxious.

“He​ ​told​ ​my​ ​mother​ ​he​ ​might​ ​not​ ​be​ ​coming​ ​back,”​ ​said​ ​his​ ​son,​ ​Joe​ ​Overstreet,​ ​who​ ​was​ ​six​ ​years​ ​old​ ​at​ ​the​ ​time.​ ​”There​ ​was something​ ​different​ ​about​ ​this​ ​mission.​ ​He​ ​knew​ ​it.”

Documents​ ​declassified​ ​in​ ​2010​ ​explain​ ​why.

Before​ ​the​ ​attack,​ ​military​ ​commanders​ ​”were​ ​aware​ ​of​ ​anomalous​ ​North​ ​Korean​ ​behavior,”​ ​according​​to​ ​a​ ​2015​ ​unclassified​ ​article​ in ​a​ ​CIA​ ​intelligence​ ​journal.​ ​National​ ​security​ ​officials​ ​knew​ ​North​ ​Korea​ ​was​ ​becoming​ ​increasingly​ ​agitated​ ​by U.S.​ ​intelligence gathering​ ​missions,​ ​but​ ​there​ ​were​ ​disagreements​ ​about​ ​the​ ​seriousness​ ​of​ ​the​ ​threats.

Overstreet​ ​briefed​ ​crew​ ​members​ ​before​ ​the​ ​flight.

“He​ ​discussed​ ​a​ ​message​ ​from​ ​the​ ​commander​ ​of​ ​US​ ​Forces​ ​Korea,​ ​warning​ ​of​ ​unusually​ ​vehement​ ​and​ ​vicious​ ​language​ ​used​ ​by the​ ​North,”​ ​the​ ​CIA​ ​paper​ ​said.

What​ ​the​ ​commander​ ​didn’t​ ​know:​ ​In​ ​the​ ​days​ ​leading​ ​up​ ​to​ ​the​ ​attack,​ ​North​ ​Korea​ ​had​ ​been​ ​quietly​ ​moving​ ​fighter​ ​jets​ ​to a​ ​base​ ​just​ ​off​ ​the​ ​coast.​ ​U.S.​ ​intelligence​ ​identified​ ​the​ ​activity​ ​as​ ​preparation​ ​for​ ​pilot​ ​training.​ ​They​ ​were​ ​wrong.

The​ ​EC-121​ ​took​ ​off​ ​unaccompanied​ ​by​ ​any​ ​protection.​ ​An​ ​Air​ ​Force​ ​tracking​ ​station​ ​monitored​ ​the​ ​flight​ ​on​ ​radar.

“Suddenly,​ ​two​ ​new​ ​blips​ ​appeared​ ​on​ ​the​ ​radar​ ​screen,”​ ​according​ ​to​ ​a​ ​1969​ ​Newsweek​ ​article​ ​on​ ​the​ ​attack.​ ​”A​ ​pair​ ​of​ ​supersonic North​ ​Korean​ ​MIG’s​ ​were​ ​closing​ ​in​ ​fast​ ​on​ ​the​ ​EC-121.”

An​ ​urgent​ ​warning​ ​was​ ​sent.​ ​But​ ​the​ ​North​ ​Koreans​ ​fired,​ ​and​ ​the​ ​American​ ​plane​ ​was​ ​destroyed.

‘Force must be met with force’

Henry​ ​Kissinger’s​ ​phone​ ​rang​ ​at​ ​1​ ​a.m.​ ​It​ ​was​ ​the​ ​duty​ ​officer​ ​at​ ​the​ ​Pentagon​ ​notifying​ ​him​ ​of​ ​the​ ​attack.

Kissinger​ ​was​ ​then​ ​a​ ​special​ ​assistant​ ​to​ ​Nixon​ ​on​ ​national​ ​security​ ​affairs.​ ​He​ ​raced​ ​to​ ​his​ ​basement​ ​office​ ​in​ ​the​ ​West Wing​ ​to​ ​gather​ ​facts​ ​before​ ​phoning​ ​the​ ​president​ ​around​ ​7​ ​a.m.,​ ​according​ ​to​ ​his​ ​memoirs.

It​ ​was​ ​the​ ​first​ ​national​ ​security​ ​crisis​ ​Nixon​ ​faced​ ​in​ ​office​ ​beyond​ ​the​ ​ongoing​ ​conflict​ ​in​ ​Vietnam.

Nixon​ ​certainly​ ​knew​ ​North​ ​Korea​ ​was​ ​a​ ​growing​ ​threat.​ ​The​ ​Pueblo​ ​incident​ ​occurred​ ​during​ ​the​ ​campaign.​ ​He​ ​assailed​ ​President Lyndon​ ​B.​ ​Johnson​ ​for​ ​not​ ​forcefully​ ​responding​ ​to​ ​what​ ​many​ ​saw​ ​as​ ​an​ ​act​ ​of​ ​war.​ ​Now​ ​Nixon​ ​faced​ ​the​ ​same​ ​dilemma.​ ​​ ​

“We​ ​were​ ​being​ ​tested,”​ ​the​ ​president​ ​wrote​ ​in​ ​his​ ​memoirs.​ ​”And​ ​therefore​ ​force​ ​must​ ​be​ ​met​ ​with​ ​force.”

But​ ​what​ ​type​ ​of​ ​force?​ ​

Johnson​ ​had​ ​considered​ ​a​ ​variety​ ​of​ ​military​ ​responses,​ ​including​ ​naval​ ​blockades​ ​and​ ​even​ ​nuclear​ ​strikes,​ ​according​ ​to​ ​declassified documents.​ ​He​ ​eventually​ ​decided​ ​it​ ​was​ ​too​ ​dangerous​ ​to​ ​respond.​ ​

In​ ​Nixon’s​ ​case,​ ​declassified​ ​documents,​ ​administration​ ​memoirs,​ ​and​ ​other​ ​scholarly​ ​research​ ​reveal​ ​an​ ​extraordinary​ ​effort throughout​ ​the​ ​government​ ​to​ ​identify​ ​a​ ​military​ ​response​ ​not​ ​just​ ​to​ ​the​ ​attack​ ​on​ ​the​ ​U.S.​ ​plane,​ ​but​ ​to​ ​any​ ​future​ ​provocations by​ ​North​ ​Korea.

The​ ​options​ ​ranged​ ​from​ ​a​ ​single​ ​targeted​ ​airstrike​ ​on​ ​North​ ​Korean​ ​airfields​ ​to​ ​a​ ​limited​ ​nuclear​ ​attack​ ​– ​code​ ​named​ ​FREEDOM DROP​ ​– ​to​ ​a​ ​full-scale​ ​nuclear​ ​war.

But​ ​it​ ​quickly​ ​became​ ​clear​ ​that​ ​even​ ​the​ ​most​ ​limited​ ​responses​ ​risked​ ​wider​ ​conflict​ ​in​ ​the​ ​region,​ ​as​ ​well​ ​as​ ​depleting U.S.​ ​military​ ​power​ ​in​ ​Vietnam.

A​ ​memo​ ​to​ ​Nixon​ ​in​ ​the​ ​hours​ ​after​ ​the​ ​attack​ ​warned​ ​of​ ​”vigorous​ ​defense​ ​measures”​ ​from​ ​North​ ​Korea​ ​targeting​ ​the​ ​U.S.​ ​military and​ ​South​ ​Korean​ ​airfields.​ ​Even​ ​as​ ​Kissinger​ ​pushed​ ​for​ ​retaliation​ ​-​- ​in​ ​his​ ​memoir,​ ​he​ ​called​ ​the​ ​administration’s​ ​response “weak”​ ​–​ ​​ ​Nixon​ ​and​ ​Pentagon​ ​officials​ ​pushed​ ​back.

“It​ ​was​ ​a​ ​calculated​ ​risk​ ​that​ ​the​ ​North​ ​Koreans​ ​would​ ​not​ ​escalate​ ​the​ ​situation​ ​further​ ​if​ ​we​ ​retaliated​ ​with​ ​a​ ​single​ ​strike against​ ​one​ ​of​ ​their​ ​airfields,”​ ​Nixon​ ​wrote.​ ​”But​ ​what​ ​if​ ​they​ ​did​ ​and​ ​we​ ​suddenly​ ​found​ ​ourselves​ ​at​ ​war​ ​in​ ​Korea?”

That​ ​had​ ​been​ ​a​ ​disaster​ ​the​ ​first​ ​time​ ​around.​ ​More​ ​than​ ​5​ ​million​ ​died​ ​in​ ​the​ Korean​ ​War.​ ​

In​ ​the​ ​end,​ ​Nixon​ ​ordered​ ​a​ ​show​ ​of​ ​naval​ ​force​ ​in​ ​the​ ​region​ ​and​ ​the​ ​resumption​ ​of​ ​reconnaissance​ ​flights​ ​–​ ​with​ ​protection.

Many​ ​people​ ​couldn’t​ ​​ ​fathom​ ​why​ ​Nixon​ ​didn’t​ ​respond​ ​with​ ​force,​ ​Overstreet,​ ​the​ ​son​ ​of​ ​the​ ​EC-121​ ​commander,​ ​recalls​ ​his mother​ ​telling​ ​him.​ ​He​ ​later​ ​became​ ​a​ ​Navy​ ​pilot​ ​and​ ​learned​ ​the​ ​military​ ​reasons​ ​why​ ​Nixon​ ​sat​ ​on​ ​his​ ​hands.

“It​ ​probably​ ​hasn’t​ ​changed​ ​that​ ​much​ ​over​ ​the​ ​years,”​ ​he​ ​said.

But​ ​Overstreet​ ​also​ ​wonders​ ​whether​ ​the​ ​lack​ ​of​ ​a​ ​forceful​ ​U.S.​ ​response​ ​for​ ​decades​ ​just​ ​keeps​ ​emboldening​ ​North​ ​Korea.

“Now​ ​they’ve​ ​gone​ ​nuclear,”​ ​he​ ​said.​ ​”I​ ​guess​ ​at​ ​the​ ​highest​ ​level,​ ​I​ ​prefer​ ​a​ ​strong​ ​stance​ ​toward​ ​North​ ​Korea​ ​over​ ​letting them​ ​do​ ​what​ ​they​ ​want.”

Nixon​ ​swore​ ​North​ ​Korea​ ​would​ ​be​ ​dealt​ ​with​ ​eventually.

“They​ ​got​ ​away​ ​with​ ​it​ ​this​ ​time,”​ ​he​ ​told​ ​Kissinger,​ ​”but​ ​they’ll​ ​never​ ​get​ ​away​ ​with​ ​it​ ​again.”

Now,​ ​decades​ ​later,​ ​another​ ​president​ ​is​ ​talking​ ​tough.​ ​Trump​ ​responded​ ​to​ ​North​ ​Korea’s​ ​threat​ ​to​ ​shoot​ ​down​ ​U.S. military planes​ ​by​ ​vowing,​ ​”I’ll​ ​fix​ ​that​ ​mess.”

“It’s​ ​called​ ​the​ ​military​ ​option,”​ ​Trump​ ​said.

He​ ​insists​ ​there​ ​is​ ​one.

CORRECTION: This story previously said that the shoot down incident on April 15, 1969, occurred four months after the Pueblo was captured. The Pueblo was captured in January 1968.

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