Ted Kennedy is a subject one brave historian might tackle one day, but that is frankly off topic (^^^) and not something I would discuss. Bobby Kennedy, on the other hand, seems to be in the middle of historical revision right now and seems a quite fit PoD as an anti-Nixon treatment or possibly a Carter replacement?
I doubt it given how this turned out elsewhere.George W. Bush successfully passes his 2006 immigration bill. This could result in an immigration backlash keeping McCain from getting the nomination in 2008, but the major effects would come in the 2010s. The US would have slightly stronger economy and anti-immigration politics would be muted because you'd have a larger population of foreign-born voters,
I doubt it given how this turned out elsewhere.
Just look at PEW Research data regarding views on immigration among Hispanics in USA: when comparing 1st generation immigrant Hispanics to US-born ones as well as Spanish-speaking ones to English or bilingual individuals it is the foreign-born & Spanish-speaking groups who are more likely to think USA has “too many” immigrants.
One that stands out at the moment would be a post-war US democratic party splitting between the Left and Right (along with the Republicans), with the UK experiencing a similar post-war split in Labour (e.g. Bevanites and Gaitskellites) and the Conservatives where the separate Blue Labour and Red Tory parties either compete against each other or merge into a new centrist party (with a similar situation unfolding in the US).
The only issue would be figuring out the list of candidates for such parties on both sides of the Atlantic from the post-war era up to the present day.
This did happen to some degree in the UK with the Social Democratic Party in 1981. An earlier split would be interesting although perhaps less likely, the only departure that comes to mind is if Bevan is elected Labour leader, although he was enough of a pragmatist to moderate his views (eg his stance on the Bomb). You probably need someone like Benn who is ideologically ruthless enough to drive social democrats out.
You would basically need to get rid of the family of that flower entirely. I do wonder if their is something else that could replace poppyseads. Both in texture and it's ability to be mashed into a past. And of course there is the pain killing applications. I wonder how it would effect the tobacco trade, and if there would be much hirer demand for it or less. Apparently many drugs, such as opium, were smoked with a bit of tobacco. Heck, I am sure their plenty of flower and grass seeds that can give you highs and lows, though some are harder to harvest than others. Incense as well, though looking at Wikipedia quickly it mentions (without citations, but understandable a person wouldn't have a book at hand with the info) that Chinese incense was burned mainly for the smoke and they type they used was odorless. Still, is people sniff markers and from paper bags filled with spray paint, I am sure there will be someone out there who can find unorthodox uses for everyday objects.No Opium. Or at least no Opium trade. ( Don't know if this is possible without ASB though)
Getting lead paint banned in America around the same time that it was banned in other countries.
And if leaded gasoline isn't invented or doesn't take off, the crime wave never happens.In that vein, the earlier you ban leaded gasoline the earlier crime rates fall.
The death of Sanjurjo OTL is a strange POD that seems easily avoidable. His place crashed on the way from Morocco to Spain because it was overloaded with too many trunks of expensive clothes, apparently he wanted to be the world's most stylish Caudillo.In 1937 Kim Philby (the Cambridge spy) was ordered by his NKVD handlers to assassinate Franco while undercover as a journalist in the Spanish Civil War. He was wounded and awarded a medal by Franco, he contemplated shooting him during the ceremony but backed out.
Ironically it was this experience of being wounded and rewarded by Franco during the Civil War that encouraged the British Secret Service to recruit him.
In that vein, the earlier you ban leaded gasoline the earlier crime rates fall.
Have Thomas Midgley die or go insane from lead poisoning --> tetraethyl lead and fluorocarbons not widespread.
Interesting butterfly effects for WW II. Especially for airpower.