WALTER, WE ARE SO FORTUNATE TO HAVE YOU JOIN TO US TALK ABOUT HENRY KISSINGER.

AND LET'S START THERE WITH THE IMAGE THAT WE SAW WITH PRESIDENT NIXON, ONE OF THE UNITED STATES' MOST CONTROVERSIAL PRESIDENTS, AND HENRY KISSINGER, ONE OF THE MOST CONTROVERSIAL DIPLOMATS IN U.S. HISTORY.

ON THE SURFACE, THESE TWO MEN COULDN'T BE MORE OPPOSITE.

YET THEY SOMEHOW WORK TOGETHER IN A SYNERGY THAT FEW U.S. PRESIDENTS WERE ABLE TO CREATE WITH THEIR ADVISERS.

CAN YOU TALK ABOUT HOW YOU EXPLAIN THAT?

>> YOU KNOW, THEY REINFORCED IN SOME WAYS THE DARK AND CONSPIRATORIAL MINDS THEY BOTH HAD.

THEY WEREN'T TOTALLY DIFFERENT.

RICHARD NIXON MADE ANTI-SEMITIC REMARKS.

KISSINGER GREW UP IN GERM 90, GOT OUT JUST BEFORE THE HOLOCAUST.

YET THEY BOTH HAD A SENSE OF POWER, THEY WERE BOTH VERY MANIPULATIVE.

KISSINGER WORKED FOR NELSON ROCKEFELLER BEFORE.

HAD HE ENDED UP BEING AIDE TO PRESIDENT NELSON ROCKEFELLER, I DON'T THINK HE WOULD HAVE BEEN AS SECRETIVE AND MANIPULATIVE.

BUT HE AND NIXON BOTH REINFORCED EACH OTHER'S DARK SIDES.

>> THEY BOTH WERE ATTRACTED TO POWER.

>> ABSOLUTELY.

AND THEY UNDERSTOOD POWER.

THEY UNDERSTOOD BALANCES OF POWER, WHICH WAS A THING THAT MADE THEM EFFECTIVE AT TIMES.

THE FIGURING OUT OF A TRIANGULAR BALANCE BETWEEN RUSSIA AND CHINA AND THE U.S., SO THAT SENSE OF POWER BALANCE THEY GOT, THEY GOT THE SENSE OF AMERICAN MORAL VALUES THAT SHOULD UNDERPIN OUR FOREIGN POLICY.

>> YOU HEAR IT IN THE INTRODUCTIONS, AS WE'VE BEEN DISCUSSING ALL DAY, HIS LEGACY.

REVERED AND REVILED.

YOU'VE HAD SEVERAL DECADES -- THE MAN LIVED TO BE 100, YET IT'S STILL VERY, VERY COMPLICATING TO DESCRIBE HIM, RIGHT?

EVEN IN ONE SENTENCE.

YOU TALK ABOUT THE JUXTAPOSITION AND THE DIFFERING VIEWS AMONG SOME OF THE WORLD'S MOST INFLUENTIAL LEADERS, EVEN ON THE NEWS OF HIS PASSING.

TONY BLAIR IN HIS EULOGY TO HENRY KISSINGER SAID HE WAS MOTIVATED BY GENUINE LOVE OF THE FREE WORLD AND NEED TO PROTECT IT.

NOW COMPARE THAT TO WHAT PRESIDENT OBAMA SAID TO "THE ATLANTIC" IN 2016.

WE'LL PICKUP IT GRAPHIC HERE.

"WE CROPPED MORE ORDNANCE ON CAMBODIA AND LAOS, YET KISSINGER WENT TO PARIS AND ALL WE HAD LEFT BEHIND WERE CHAOS, SLAUGHTER AND GOVERNMENTS THAT OVER TIME HAVE EMERGED FROM THAT HELL.

WHEN I GO TO VISIT THOSE COUNTRIES, I'M GOING TO TRY TO FIGURE OUT HOW WE CAN HELP THEM REMOVE BOMBS THAT ARE STILL BLOWING OFF THE LEGS OF LITTLE KIDS.

IN WHAT WAY DID THAT STRATEGY PROMOTE OUR INTERESTS?"

BETWEEN THESE TWO DESCRIPTIONS AND THOUGHTS ON HENRY KISSINGER, WHICH ONE DO YOU VIEW AS HIS BIOGRAPHER MORE CLOSELY ALIGNED WITH THE MAN HIMSELF?

>> I THINK IN THE END, IT WILL BE A MORE PROBLEMATIC LEGACY.

BECAUSE HE DID THINK THAT GREAT POWER DIPLOMACY COULD AFFECT THESE -- WHETHER EAST TIMOR OR CHILE OR VIETNAM, CAMBODIA, LAOS, HE SAW IT ALL IN THE CONTEXT OF A GREAT POWER STRUGGLE, AS IF HE WERE ONE OF HIS HEROES, BISMARCK, ONE OF THE EUROPEAN FOREIGN MINISTERS IN THE 1800s.

AND IN THE END, IT CAUSED A WHOLE LOT OF CIVILIAN CASUALTIES THAT ARE TENFOLD THE NUMBER THAT WE'RE SEEING IN THE MIDDLE EAST, A HUNDREDFOLD THE NUMBER.

GENOCIDE, WHETHER IT WAS LAOS, CAMBODIA, THE BOMBINGS THERE, THINGS THAT HAVE BEEN FORGOTTEN LIKE EAST PAKISTAN AND TIMOR.

ALL THESE PLACES GO UP IN FLAMES BECAUSE KISSINGER TRIED TO PUT IT INTO A FRAMEWORK OF THE SUPERPOWER COLD WAR STRUGGLE.

>> HE WAS MASSIVELY CREDIT SYTHED FOR ACTIONS IN CAMBODIA, BOMBING TO ERADICATE THE VIET CONG FORCES, "STRIKE ANYTHING THAT FLIES, ANYTHING THAT MOVES."

HE'S BEEN ACCUSED OF GENOCIDE, BREAKING INTERNATIONAL LAWS.

TENS OF THOUSANDS OF CIVILIANS KILLED.

DID HE EVER SEEM TO EXPRESS REGRET FOR HIS PAST ACTIONS?

EVEN IF THEY WERE WELL INTENTIONED, IN HIS MIND AT LEAST, TO YOU?

>> I THINK HE EXPRESSED THE SENSE THAT THEY HAD GOTTEN IT WRONG.

CLEARLY IF YOU LOOK AT CAMBODIA, THAT'S THE WORST.

THEY DID SECRET INVASION -- THEN THE SECRET BOMBING OF CAMBODIA, IT WAS CALLED.

BECAUSE KISSINGER OPERATED IN GREAT SECRECY.

BUT IT WAS NO SECRET TO THE CAMBODIANS.

THEY WERE BEING BOMBED.

HUNDREDS OF THOUSANDS OF CIVILIANS WERE KILLED.

AND NOWADAYS WE LOOK AT WHAT'S HAPPENING IN GAZA AND OTHER THINGS AND WE WORRY ABOUT CIVILIAN CASUALTIES.

THAT WAS NOT ON HIS RADAR SCREEN.

WHEN YOU COME OUT OF THAT, YOU END UP WITH A GENOCIDE AND CHAOS IN LAOS, CAMBODIA, ALL OF SOUTHEAST ASIA.

SO HE KNEW IT DIDN'T WORK.

I THINK HE WOULD ARGUE THAT HE WAS WELL INTENTIONED, THAT IT WAS TO TRY TO GET US OUT OF THE VIETNAM WAR.

BUT CERTAINLY SOMEBODY WITH HIS BRILLIANT MIND KNOWS THAT IT ENDED UP BEING A REALLY BAD STRATEGY.