I've been going to the match home & away for 60 years. There has been varying degrees of hooliganism during all that time. From brief recollections, WHU V EFC in the early 60's, we lost 1 nil, I wasn't there but the TV showed a Blue who invaded the pitch after the WHU goal & fought with the Met bizzies. Rangers at Goodison (1963), bottles getting chucked around, pissed up jocks everywhere. Man Utd away 1966 there was a load of fighting in the Stretford End at half time. WHU away 1968, a Monday night game we won 4-1, and the first time I ever left an away ground (still in mid teens) to be confronted by a mob - West Ham mods/skins waiting outside to attack those Blues who'd made the journey. Then it started to rack up around the country, 1969 away at Newcastle mid week, we won & a big mob bricked the Sunnyways & Crown coaches (I was on Home James & the driver did one just in time). So, on & on, getting worse at virtually every game into the 70's & 80's (attendances generally plummeted). It never ended, although the all seater & Police operations targeting the 'organisers' had an effect. Onto the smaller mobs who'd arrange stuff away from the ground. Anderlecht away in about 2002(?) in a pre season friendly - walked out of the ground, down some pokey exit path towards the road after the final whistle with my young son into a load of CS gas hovering in the air - apparently, we were told by others affected, that a load of our lot had bailed out early looking for trouble, attacked the Belgian police & went on a rampage. We've all heard tales of some of the things that have happened like the so-called 'Battle of Everton Valley', & infamously the relatively recent Millwall away game.
We've all read reports of foreign Ultras targeting supporters of English teams, usually the evening before a match in an unexpected attack on a bar - nothing to do with politics. Unfortunately if you love following any team it is inevitable there is a chance of trouble occurring near to you at some time, trying to avoid it means keeping your wits at all times & staying away from certain locations, not easy!
It doesn't matter who is in Government, hooligans love trouble. It's not rocket science though that evidence of increasing hooliganism coincides with less Police at matches, that is a result of politics, with less being available for footy policing due to a big reduction in Police numbers. The Cons may be in power now, but I doubt there would be much difference in Police staffing if Labour, LibDems or the Greens were in power.