What's wrong with multi-party system

In his NYTimes column article with the title of "Who Will Tell the
People?", Thomas Friedman explained the decline of American power,

"[we are] not as powerful as we used to be because over the past three
decades, the Asian values of our parents=92 generation =97 work hard,
study, save, invest, live within your means =97 have given way to
subprime values: =93You can have the American dream =97 a house =97 with
no
money down and no payments for two years.=94"

The following also caught my attention.

"Much nonsense has been written about how Hillary Clinton is
=93toughening up=94 Barack Obama so he=92ll be tough enough to withstand
Republican attacks. Sorry, we don=92t need a president who is tough
enough to withstand the lies of his opponents. We need a president who
is tough enough to tell the truth to the American people. Any one of
the candidates can answer the Red Phone at 3 a.m. in the White House
bedroom. I=92m voting for the one who can talk straight to the American
people on national TV =97 at 8 p.m. =97 from the White House East Room."

The above says a lot on what's wrong with American democracy. In the
current two party set up, political leaders often respond to the
opposite party rather than to the needs and wants of the poeple. In
this case, Friedman found Clinton's claim that she was toughening up
Barack Obama against future Republican attacks bogus. Simply put, such
nonsense changes the responsibility of the U.S. presidency from
responding to the people to responding to the opposition.