WILLIAM: IN A MAJOR VICTORY FOR THE INCOMING PRESIDENT, REPUBLICANS WILL NOW CONTROL BOTH HOUSES OF CONGRESS AFTER THE HOUSE WAS CALLED FOR THE GOP EARLIER THIS WEEK.

BUT THIS TRIFECTA DOESN'T GUARANTEE SMOOTH GOVERNING.

AS WITH TRUMP'S FIRST TERM, NARROW MARGINS IN THE SENATE AND HOUSE COULD MAKE PASSING MAJOR LEGISLATION DIFFICULT.

SO WHAT WILL IT TAKE TO GOVERN IN THIS DIVIDED TIME?

CASEY BERG IS THE DIRECTOR OF THE LEGISLATIVE AFFAIRS PROGRAM AT THE GRADUATE SCHOOL OF POLITICAL MANAGEMENT AT GEORGE WASHINGTON UNIVERSITY.

IT'S SO GOOD TO HAVE YOU ON THE PROGRAM.

AS WE HAVE SAID, TRUMP NOW CONTROLS BOTH HOUSES OF CONGRESS.

WHEN YOU COUPLE THAT, AND HE HAS GOT THE WHITE HOUSE.

COUPLE THAT ALSO WITH WINNING THE POPULAR VOTE.

IT SEEMS LIKE HE HAS ENORMOUS FREEDOM TO DO WHAT HE WANTS.

BUT THAT IS, AS WE KNOW, NOT ALWAYS HOW IT WORKS OUT.

CASEY: ABSOLUTELY.

THE PRESIDENT, ESPECIALLY ONE WHO WINS THE POPULAR VOTE, HAS BOTH CHAMBERS OF CONGRESS IN HIS POCKET, HE CAN BE INCREDIBLY AGGRESSIVE.

AND WE'RE EXPECTING PRESIDENT TRUMP TO DO EXACTLY THAT.

BUT HIS POWERS ON THE EXTEND AS FAR AS THE MEMBERS OF CONGRESS ALLOW THEM TO GO.

SO AS WE SAW WITHIN THE FIRST TERM, HE HAD THE UNITED GOVERNMENT THERE, BUT HE WAS CHECKED A COUPLE OF TIMES ON NOMINATIONS, POLICY ONCE.

AND IT DOESN'T JUST GO AS SMOOTHLY AS WE THINK IT SHOULD GIVEN THAT GOP HAS ALL THE LEVERS OF CONTROL IN TERMS OF GOVERNMENTAL POWER.

WILLIAM: I GUESS IT DEPENDS ALSO WHERE YOU SIT ON THE POLITICAL SPECTRUM, THAT'S EITHER A FEATURE OF THE SYSTEM OR THAT'S A BUG IN THE SYSTEM.

CASEY: EXACTLY.

WE ARE TAUGHT FROM OUR YOUNGEST DAYS THAT WE HAVE CHECKS AND BALANCES.

THAT'S THE GENIUS OF OUR SYSTEM.

AND THAT'S TRUE TOO EVEN IF EVERY LEVER OF GOVERNMENT IS CONTROLLED BY THE SAME PARTY.

IT'S NOT JUST AS SIMPLE AS HAVING THE SAME LABEL NEXT TO YOUR NAMES AND YOU GET WHAT YOU WANT.

IT DEPENDS WHAT EXACTLY YOU'RE TRYING TO DO AND HOW AGGRESSIVE YOU'RE TRYING TO BE DOING IT.

WILLIAM: TRUMP HAS BEEN ANNOUNCING SEVERAL OF HIS CABINET NOMINEES THIS WEEK.

AND EVEN WITHIN THE GOP, SOME OF THOSE PEOPLE ARE VERY, VERY CONTROVERSIAL.

DO THESE NARROW MARGINS LIKELY IMPACT TRUMP'S ABILITY TO GET PEOPLE IN PLACE THAT HE WANTS?

CASEY: 100%.

IF YOU HAVE A DIVIDED GOVERNMENT OR HAVE A SMALL MAJORITY, PARTICULARLY IN THE SENATE WHO CONFIRMS THESE BOATS, EVERY -- CONFIRM THESE FOLKS, EVERY VOTE MATTERS.

YOU CAN'T AFFORD TO LOSE SEVERAL SENATORS.

AND SO EACH SENATOR WILL TRY TO USE THIS AS A LEVER TO TRY TO MAKE SURE THAT THE PRESIDENT AND THEIR NOMINEES ARE CONFORMING TO WHAT THEY EXPECT THEM TO DO IN OFFICE.

BUT IF YOU LOSE JUST A COUPLE OF VOTES ON YOUR SIDE, KNOWING THAT DEMOCRATS ARE NOT GOING TO HELL.

WILLIAM: AND SO WHAT IS YOUR SENSE WHEN YOU, AS SOMEONE WHO HAS LOOKED AT POLITICAL HISTORY OF AMERICA GOING BACKWARDS, WHAT DO YOU IMAGINE UNFOLDING OVER THE JUST IN THE SHORT TERM, BUT THEN OVER THE FOUR YEARS OF THIS ADMINISTRATION?

CASEY: SO RIGHT NOW, I'M WATCHING HOW MUCH PUSHBACK SENATE REPUBLICANS ARE HINTING AT GIVEN THE NOMINATIONS COMING FORWARD.

AND RIGHT NOW, WE DON'T HAVE THE SPECIFICS OF EXECUTIVE ORDERS OR WHAT POLICIES THEY'RE GOING TO GO THROUGH.

BUT EVERY INDICATION IS RIGHT NOW, INCLUDING FROM INCOMING SENATE MAJORITY LEADER JOHN THUNE, THAT THEY'RE IN SUPPORT OF THE AMERICA FIRST TRUMP AGENDA.

BUT THAT'S ALL MESSAGING SO FAR UNTIL WE GET THE SPECIFICS OF EXACTLY WHAT THEY WANT TO DO AND HOW AGGRESSIVE THEY WANT TO BE.

IF THEY START DISAGREEING WITH HOW FAR THE PRESIDENT WANTS TO GO, THEN WE'RE GOING TO START TO SEE SOME PUSHBACK WILLIAM: ON THAT SAME FRONT, I MEAN, TRUMP HAS EXPRESSED A VERY EXPANSIVE AND AGGRESSIVE USE OF EXECUTIVE AUTHORITY.

AND WE KNOW HE'S GOT PEOPLE AROUND HIM THAT BELIEVE IN THAT.

DO YOU FORESEE THE TRUMP ADMINISTRATION CHANGING IN ANY FUNDAMENTAL WAY THE BALANCE OF POWERS, THESE CHECKS AND BALANCES?

CASEY: WELL, THIS IS A CONTINUING TREND, THAT PRESIDENTS OF BOTH PARTIES HAVE CLAWED AWAY SOME OF POWERS THAT WE HAVE HISTORICALLY ASSOCIATED WITH CONGRESS.

THE POWER TO DECLARE WAR, TO EXECUTE FOREIGN ACTIVITIES ON OTHER SOIL.

AND THEN JUST TAKING A LEAD IN POLICYMAKING FROM THE OVAL OFFICE, MOSTLY THROUGH EXECUTIVE ORDERS.

AND IT'S UP TO CONGRESS TO CLAW THAT POWER BACK, TO STOP THEM FROM GOING TOO FAR, FROM DENYING THEM THEIR EXECUTIVE ORDERS, MAYBE EVEN GOING TO THE COURTS TO MAKE SURE THAT THE PRESIDENT DOESN'T OVERREACH.

BUT RIGHT NOW, WE'RE NOT SURE HOW WILLING CONGRESSIONAL MAJORITIES, PARTICULARLY REPUBLICANS, ARE GOING TO LET PRESIDENT TRUMP GO.

SO NOW WE'RE GOING TO SEE ROUND TWO OF THIS.

AND NOW HE HAS EXPERIENCE DOING THE JOB AND A BRAND NEW CONGRESS ELECTED ON THE TRUMP AGENDA.

WILLIAM: TRUMP ALSO LIKES TO POINT OUT, LOOK, HE GOT 75 MILLION VOTES.

THE DEMOCRATS, YOU KNOW, THE HARRIS CAMPAIGN ALSO SAYS, WELL, LOOK, WE GOT 72 MILLION VOTES.

YOU COULD LOOK AT THAT AND SAY TRUMP IS CLEARLY DOMINANT.

AND YOU COULD ALSO LOOK AT THAT AND SAY THAT IS STILL A NARROW DIVISION IN THIS COUNTRY.

DO YOU SEE ANY POTENTIAL THAT THE REPUBLICANS AND DEMOCRATS WILL ACTUALLY WORK TOGETHER, OR DO YOU THINK THAT'S JUST A NAIVE FANTASY?

CASEY: WELL, HERE'S THE LITTLE KNOWN SECRET OF CAPITOL HILL, IS THAT TO GET BIG THINGS DONE, YOU NECESSARILY NEED BIPARTISAN AGREEMENT.

THERE'S VERY LITTLE THAT CAN BE DONE ON A SIMPLE MAJORITY BASIS, PARTICULARLY IN THE SENATE, UNLESS THEY THROW OUT THE FILIBUSTER.

REPUBLICANS AND DEMOCRATS ARE GOING TO HAVE TO WORK TOGETHER.

AND THEY HAVE IN THE PAST, DESPITE BEING THIS OVERRIDING NARRATIVE OF DYSFUNCTION, POLARIZATION WITHIN OUR LEVELS OF GOVERNMENT.

AND SO IF PRESIDENT TRUMP WANTS TO MAKE BIG INSTITUTIONAL OVERHAULS, THEY'RE EITHER GOING TO HAVE TO GET RID OF THE FILIBUSTER OR THEY'RE GOING TO HAVE TO WORK WITH DEMOCRATS.

WILLIAM: YOU DO HEAR PEOPLE SAY WE LIVE IN SUCH A POLARIZING TIME, BUT THIS COUNTRY HAS SEEN EVEN MORE INTENSE POLARIZATION.

WE CAME TO WAR WITH EACH OTHER ONCE UPON A TIME.

DOES HISTORY OFFER ANY LESSONS ABOUT THE PROPER ROLE FOR A LEADER IN A PARTIZAN, POLARIZED TIME?

CASEY: REALLY, POWER IS IN THE EYE OF THE BEHOLDER, PARTICULARLY FOR PRESIDENTS, WHERE THE PERSONALITY, THE CHARACTER OF THE PERSON OFTEN TAKES OVER THE OFFICE ITSELF.

AND SO WE CAN SEE THIS GOING BOTH WAYS.

HISTORY HAS SAID THAT WE HAVE SNAPPED BACK FROM CRIPPLING LEVELS OF POLARIZATION, DANGEROUS LEVELS.

BUT IT DOESN'T HAVE TO GO THAT WAY.

IN FACT, THEY CAN OFTEN EXACERBATE THOSE DIVISIONS TO THEIR POLITICAL ENDS.

POINTING TO THE OTHER SIDE AND CALLING THEM THE ENEMY, MAKING SURE THAT OTHER AMERICANS ARE SEEN AS LESS THAN OR DANGEROUS.

SO REALLY, THE PRESIDENT CAN BE A UNIFYING FORCE IN HIS RHETORIC AND WHAT MESSAGE HE TRIES TO SEND, EVEN WHAT POLICIES HE TRIES TO PURSUE.

BUT IT CAN ABSOLUTELY GO THE OTHER WAY.

WILLIAM: CASEY BURGAT OF GEORGE WASHINGTON UNIVERSITY, THANK YOU SO MUCH FOR YOUR INSIGHT.

CASEY: ABSOLUTELY.

THANK YOU.