HARI SREENIVASAN: From the
White House to Capitol Hill.

For seven months, congressional
Republicans have taken a
sharply partisan route on health

care.

They have made several attempts
to repeal and replace the
Affordable Care Act, which

have failed.

But why did Republicans go
partisan in the first place?

It's part of a cultural
shift in Congress years in
the making for both parties.

Our Lisa Desjardins explains.

LISA DESJARDINS: Congress these
days has an obvious theme.

SEN.

BERNIE SANDERS (I),
Vermont: I should think
that every Republican
should be embarrassed.

MAN: Our Democratic friends
are trying to make it more
difficult for President Trump

to do his job.

SEN.

CHUCK SCHUMER (D-NY), Minority
Leader: We urge our Republican
colleagues to change their

tune.

LISA DESJARDINS: More blame
than legislation on the floor.

Veteran GOP Senator Susan
Collins of Maine has
long been considered one
of its most bipartisan

members, but she admits
it's becoming harder.

SEN.

SUSAN COLLINS (R), Maine: We are
in a time of hyper-partisanship
that is unlike any other

that I have seen in
my time in the Senate.

LISA DESJARDINS: Some
examples this year?

Republicans going it alone on
health care, with a partisan
House vote and a Republican-only

closed-door process in
the Senate, Democrats
forcing symbolic late-night
sessions and boycotting

committee hearings,
slowing the legislative
process to a near stop.

And this month, Republican
Majority Leader Mitch
McConnell blamed
Democrats for his decision

to postpone the
Senate's August recess.

SEN.

MITCH MCCONNELL (R-KY),
Majority Leader: Due
to this unprecedented
level of obstruction

that we have been experiencing,
we will be in session the
first two weeks of August.

LISA DESJARDINS: All just five
weeks after this: a gunman
opening fire on a Republican

baseball practice, leaving House
Majority Whip Steve Scalise
initially in critical condition,

and still recovering.

The attack brought a chorus
of calls for bipartisanship.

REP.

NANCY PELOSI (D-CA), House
Minority Leader: We are not
one caucus or the other in this

House today.

REP.

PAUL RYAN (R-WI), Speaker
of the House: We are united.

LISA DESJARDINS: Later that day,
the managers of the Republican
and Democratic teams urged

an end to the sharp divide.

REP.

JOE BARTON (R), Texas: We
have an R or a D by our name,
but our title -- our title is

United States representative.

LISA DESJARDINS: We caught up
with Representatives Joe Barton
and Mike Doyle again, and asked

if things have changed.

REP.

MIKE DOYLE (D), Pennsylvania:
There's no cure for this.

And it's not just
our responsibility.

Bipartisanship either gets
fanned or, you know, encouraged
by outside forces, too.

LISA DESJARDINS: But both
say too many members get
attention now with sharp words.

REP.

JOE BARTON: At the end of
every two years, do you want
to go home and say, man, I gave

a heck of a press conference,
or do you want to put something
else on your wall, that you

have got a bill signed into law?

LISA DESJARDINS: Barton admits
he was once a young bomb
thrower, and accepts some blame

for his party.

REP.

JOE BARTON: When I got elected,
I joined the Gingrich group.

So I was a part of the
problem at the time.

LISA DESJARDINS: In the
1994 Republican Revolution,
then-new Speaker Gingrich
made partisan battles

a central strategy.

Years later, in 2013, Democrats
upped the partisan ante,
changing Senate rules to push

through some nominees
with no Republican votes.

Of course, partisanship, even
partisanship, is as old as
Congress itself, from duels,

to a near fatal beating inside
the Senate chamber, to this
staircase outside the House

chamber, where you can still
see what is said to be blood
stains from where a newspaper

reporter shot a former
member of Congress in 1890.

But divide can have a
purpose, says Amy Walter of
The Cook Political Report.

AMY WALTER, The Cook
Political Report: I don't
think partisanship in
and of itself is a bad

thing.

The challenge is when that
alone is what prevents
people from working
together to do other things.

LISA DESJARDINS: Part of the
trouble, fewer moderates.

Data from The Cook Political
Report shows that, 20 years
ago, more than a third of all

House districts were
moderate, voting similarly
to the nation as a whole.

But, since then, House districts
have become more partisan,
red or blue, and the number

of moderate or swing
seats has fallen by half.

AMY WALTER: And they have all
been replaced by ideologues
either on the left or the right.

LISA DESJARDINS: One reason,
special interest groups on the
left and the right are spending

record amounts of money
in ads, and increasingly
scoring lawmakers' votes
on sometimes narrow

issues.

Again, Susan Collins:

SEN.

SUSAN COLLINS: Unfortunately,
there's a lot of pressure
from outside special interest

groups to toe the party line.

They want 100 percent fidelity,
100 percent of the time, to
100 percent of their views.

And, if you deviate, you are
going to feel the consequences.

LISA DESJARDINS: All
this underscores how a
major issue like health
care remains unresolved,

and it sets up a great struggle.

To get anything done,
Republicans in power may soon
have to work with Democrats.

For the "PBS NewsHour,"
I'm Lisa Desjardins.