I recently commented that the last time I felt such a divergence between the two Americas - liberal and conservative - was during the Vietnam War. On Wednesday night, this polarisation manifested itself in the riots at UC Berkeley.
Berkeley saw the birth of a wave of anti-establishment protests in the Sixties, culminating in shootings by the National Guard of four innocent students at Kent State University, Ohio. At the time, I was a busy 24-year-old, touring the States to promote my developing rock groups. It affected me deeply.
Nowadays, social media plays an integral role in amplifying the anger felt by those horrified by the first steps taken by the Trump Administration, and allows vast swathes of protestors - radical or otherwise - to organise in no time at all. Heaven knows what would have happened had Twitter, Facebook and WhatsApp existed at the height of antipathy towards US foreign policy in south-east Asia.
We are once again living in a deeply divided world. Polarisation over President Trump in the US, and Brexit in the UK, is intensifying rather than abating. Whatever Theresa May might say, this country is far from "coming together".
Despite a petition calling on the Prime Minister to cancel Trump's proposed state visit attracting over one million signatures, a YouGov poll found that 49 per cent of Brits are in favour of the President making this trip. A very similar percentage of Americans - 45 per cent, according to CBS - approve of the controversial 'travel ban' which will temporarily bar citizens of seven predominantly Muslim countries entering the United States. Everywhere we look, on almost every conceivable issue, the public are split almost exactly down the middle.
But unlike the Sixties, where the diametrically opposed left and right clashed so dramatically, today the battle lines are drawn between reactionary extremes at either end of the ideological spectrum, and the moderate centre ground. Brexit was backed by both right-wing Conservatives and traditional, working class Labour voters. Trump was elected by a similar coalition. Concerns over issues as diverse as immigration, the pace of technological change, economic liberalisation and climate change, have served to unite these two hitherto opposed groups.
At the highest level of politics, we have seen the once-prevailing liberal elite repudiated by electorates in several western democracies. An era which saw the moderate, pro-European John Major replaced by successive moderate, pro-Europeans in Tony Blair, Gordon Brown and David Cameron, is well and truly over. Gone are the days when would-be election winners had no choice but to appeal to the centre.
In 2017, moderate centrists are disconnected and disenfranchised, struggling adjust to the new normal. Instead it is those who once languished on the fringes - the 40-something per cent - who hold the cards. Trump's state visit will go ahead; Article 50 will be triggered. The old Blairite refrain, "things can only get better", never sounded so distant.