Trying to make a straight hierarchical list is pointless- and not meaningful to you.
Just as a little reality check: If your priority is name value. and you only want “Ivy” you may not have the choice as to which country you study in, even if you are predicted a 45. Acceptance rates at the “Ivy League” schools are in the very very low single digits for international students, and applications are evaluated on a holistic basis. On the other hand a high IB prediction will get you most of the way into any of the UK unis (except Oxbridge, which have aptitude tests for most subjects, and require interviews).
For name recognition (in the full awareness that this is the sort of parlor game for which there is no one ‘right’ answer)::
In the US, US > UK > RoW. In the UK, UK + Harvard > US + a handful of major international unis > RoW. For the RoW it is Harvard + Oxford + their top local unis > a subset of the names you have already listed (varies by where in the world) + UC-B / UCLA > Random top-tier unis that the person has heard of > everybody else
For job hunting it will matter where you have the legal right to work: the US will expect you to get gone pretty fast after you finish your undergrad. The UK used to have a pathway to staying, but in the wonderful world of Brexit all bets are off.
For Politics / IR you will need a Masters. The top tier of US masters programs will expect ~3 years of work experience, and they are typically 2 years. The UK programs are typically 1 year and they are not as fussy about work experience.