There have been many takes on why the Republican plan to repeal and replace Obamacare failed. This is part of Nate Silver's explanation at fivethirtyeight.com:
While most reporting has focused on the House Freedom Caucus’s objections, the AHCA also faced significant dissent from moderate Republicans, perhaps enough to kill it.
According to The New York Times’s whip count, 29 of 58 Republican moderates in the House either planned to vote against the bill or were undecided on it. Only 10 of those 29 moderates were firm “no” votes, but it’s possible that most of the undecideds would have turned against the bill as debate continued, especially if it were rewritten to placate the Freedom Caucus. Throughout the day on Thursday and Friday, moderates such as New Jersey Rep. Rodney Frelinghuysen came out of the woodwork to oppose the bill as Trump and Ryan sought to whip the Freedom Caucus into shape.
" data-footnote-id="1" style="border: 0px; box-sizing: border-box; font-family: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; margin: 0px; padding: 0px; position: relative; text-decoration: none; text-rendering: optimizelegibility; vertical-align: baseline;" href="https://fivethirtyeight.com/features/trump-doesnt-have-a-mandate-for-paul-ryans-agenda/#fn-1" class="espn-footnote-link">1 And considering that the bill would almost certainly have faced resistance from moderates in the Senate even if it had passed the House — and that no Democrats in either chamber had pledged to support it — the narrative that the Freedom Caucus was principally responsible for the bill’s demise is at least a little dubious. The more fundamental, Politics 101 problem is that Ryan drafted a bill that was too far removed from what voters actually wanted. If the bill wasn’t killed by moderate Republicans, it was probably going to exact a significant electoral penalty on the GOP, like the one Democrats endured after passing Obamacare in 2010. And then there’s Trump. His philosophy toward the size and scope of government has never been clear, exactly. But from the hints he’s given — such as in advocating for a trillion-dollar infrastructure plan — he tends more toward the center than either the Ryan or the Freedom Caucus wings of the GOP. Trump was elected without much of a mandate, given his narrow margin in the Electoral College and his loss in the popular vote. But congressional Republicans didn’t have much of a mandate, either. Although people seemed to forget about it as they focused on Trump’s upset win at the top of the ticket, Republicans lost seats in both the House and the Senate in last year’s elections. How many congressional seats a party gains or loses when it takes over the White House is a good measure of whether there was an overall mandate for the party’s agenda or instead the presidential result reflected a more incremental (and perhaps quirky or circumstantial) victory. Among the 11 times in the past century when the presidency changed parties, Warren G. Harding in 1920, Franklin D. Roosevelt in 1932, Ronald Reagan in 1980 and Barack Obama in 2008 all came into office with major gains for their party in Congress and a lot of wherewithal to enact sweeping changes. Trump, George W. Bush, Bill Clinton, Jimmy Carter and John F. Kennedy did not, by contrast. Dwight Eisenhower and Richard Nixon were somewhere in between. Unsurprisingly, there’s a correlation between a party’s gains or losses in Congress and the margin of its presidential victory. But it isn’t a perfect one. Clinton won the Electoral College fairly definitively in 1992, but his Democrats lost nine seats in the House and only broke even in the Senate. Eisenhower’s congressional gains were modest given his landslide presidential victory, meanwhile. You could interpret that as meaning Eisenhower and Clinton were elected more on their personal qualities — Eisenhower’s résumé, Clinton’s personality — than on the basis of their party’s agendas. And that was reflected in the policies they pursued. Eisenhower was one of the most centrist presidents of all time, while Clinton ran — and mostly governed — as a “New Democrat,” somewhat against his party’s tax-and-spend reputation. Trump isn’t in the Eisenhower or Clinton category because his own electoral performance was underwhelming, just as his party’s was in Congress. Instead, the better comparison is to George W. Bush, who like Trump lost the popular vote and also saw his party lose seats in Congress. But Bush also governed in a fairly bipartisan fashion early in his termCheck out the conciliatory notes in his inaugural address or in his first address to Congress.
" data-footnote-id="2" style="border: 0px; box-sizing: border-box; font-family: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; margin: 0px; padding: 0px; position: relative; text-decoration: none; text-rendering: optimizelegibility; vertical-align: baseline;" href="https://fivethirtyeight.com/features/trump-doesnt-have-a-mandate-for-paul-ryans-agenda/#fn-2" class="espn-footnote-link">2 before moving to the right after the Sept. 11 attacks. Instead of offering a centrist or a populist solution, however, the AHCA gave voters a bill that nobody was asking for. Republicans have been running on repealing and replacing Obamacare for seven years, and they’ve won a lot of elections in that period. You can argue that they have a mandate on the issue, even if they don’t have one overall. But Ryan and Trump pretty much ignored where public opinion stands on health care. Medicaid, which the AHCA would have rolled back, is extremely popular, for instance. About two-thirds of voters support government funding for Planned Parenthood; the AHCA would have cut it. But the bill didn’t do much to address the problems voters were actually concerned about, such as rising premiums. Furthermore, Ryan and Trump advanced this bill despite receiving a warning shot from the public: Obamacare had almost immediately become more popular after Trump won the election. I don’t recall a lot of other times when public opinion shifted so quickly on a bill in response to an election result.The election was almost certainly the cause; it wasn’t as though Obamacare was getting a lot of good headlines last fall.
" data-footnote-id="3" style="border: 0px; box-sizing: border-box; font-family: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; margin: 0px; padding: 0px; position: relative; text-decoration: none; text-rendering: optimizelegibility; vertical-align: baseline;" href="https://fivethirtyeight.com/features/trump-doesnt-have-a-mandate-for-paul-ryans-agenda/#fn-3" class="espn-footnote-link">3 It was as though voters were throwing up a big yield sign to congressional Republicans — we didn’t expect Trump to win the election; instead, we elected you to serve as a check on Hillary Clinton, so proceed with caution. Ryan barreled right on through it.