Here are some short points towards that:
1. In an erratic and unpredictable situation, electoral victory boils down to enthusiasm
Trump took the Presidency because his voters believed in him and the vision they shared. Trump's voters are potentially far fewer than Clinton's. But their powerful vision of a protectionist America carefully limiting access to domestic rights is an increasingly potent one.
2. Trump got the same number of votes as Romney (who lost). Clinton got seven million fewer votes than Obama. Trump didn't win - Clinton lost. The campaign itself must take some responsibility
While Trump galvanised his smaller pool of voters, the Democrats put theirs off. Voter turnout fell dramatically and the losses were all Clinton's. If she had tacked convincingly to the left after defeating Sanders in the primary she would have won. This was a tragic strategic error. Equally shocking is that Trump's extremist, anti-Muslim rhetoric took the entire Republican base with him.
3. Trump's victory signals the collapse of the centre
You'll hear a lot about this, but it will be explained in terms of the pathologies of working class voters. This is inadequate. American society is in crisis. At its root is the long-term transformation of the US economy, but its form is a crisis of political representation. Turnout is around 50% - a catastrophe for any kind of legitimacy for the incoming administration. The US establishment has lost its power to tell persuasive stories about itself and the world. That vacuum is being filled with all kinds of seething misogynistic, racist and homophobic resentments.
4. The US state and most of its governing institutions are also in a crisis of neoliberalism, one connected to the crisis of US society
The US state's tax base has shrunk, privatisations and outsourcing have reduced public oversight, and law enforcement has become increasingly militarised to deal with the constant social upheaval caused by the retreating state. The US fiscal model has long been characterised by over investment in military innovation and stagnation and under investment in public services like health. This has produced inertia and corruption at every level of US public life, producing a rich array of morbid symptoms, from NSA spying to an obstructionist, right-wing fundamentalist Republican Party. Trump's victory has to be seen in light of this catastrophic breakdown of state functioning and legitimacy. Likewise with the failure of the political class to introduce long overdue reforms to Wall Street and the electoral system. Remember: Clinton won the popular vote. She got more votes than Trump, despite her losing seven million voters. Yet she lost.
5. The US media's revenue model is collapsing, and its fixation on Trump is a result
Already today the New Statesman is running an article about how social media is responsible for Trump. This is a flagrant lie. In March this year CBS CEO Les Moonveswas secretly recorded saying, "Trump may not be great for America, but he's great for us... Sorry. It's a terrible thing to say. But, bring it on, Donald. Keep going." Trump is a creation of the traditional media, who depoliticised and decontextualised his every statement, treating it as part of a fun, ratings-boosting circus. They offered little to no analysis of why Trump was winning. At one point when the two candidates were almost level in the polls, ABC World News Tonight had devoted just one minute of air time to the Bernie Sanders campaign compared to eighty-one for Trump. The traditional media helped Trump every step of the way in their desperation for ratings. This was not primarily to do with social media.
6. Polls weren't that wrong - but interpretation was
HuffPost was giving Clinton a 91% chance of victory on the strength of poll data that put her on average two points ahead of Trump. Those polls were within the margin of error and they should have been read as such. Data on early voting also suggested young people and black voters weren't showing up even in their previous relatively low numbers. This was ignored. Everyone was convinced the Clinton's electoral machine would pummel Trump. What was missing was any account of enthusiasm on the Trump side and the politics surrounding it. Shallow obsessions with scandal and electability led to a decontextualisation of Trump and a complete absence of political analysis. Yet again the liberal centre was proved wrong and the simple reason is because its constituencies are collapsing and its ability to understand or represent the world falling to pieces.
7. Because it is rooted in these crisis conditions, Trumpism won't exhaust itself. It will have to be killed.
Another way of saying this is that Trumpism didn't just happen - it had causes. An you won't be able to bury your head in the sands and wait for Obama 2.0 so that everything can go back to normal. Trumpism feeds on despair and demoralisation. So those opposing him need an alternative. And while the promise of social justice and equality will be crucial to that, it is in politics that people experience inequality. The left has relearnt how to talk about social inequality. But it needs to talk about democracy too - after all, this is both a social crisis and a crisis of political representation in and beyond the state. The left must offer dignity to all, and the way it achieves that will be through rebuilding democracy from the ground up.