AO1: UK parties tend to vote together on most issues because of stronger party discipline AO2: There are deep ideological divisions with UK parties over issues which also divide UK society, e.g. Brexit AO1: US parties will unite more often around core ideological goals or fundamental policies such as abortion AO2: US parties are also deeply divided over key issues - often social issues - such as abortion and gun control, which prevents a coordinated approach to policy AO1: Parties in both countries are more likely to be united at conference/national party conventions AO2: US parties are broad coalitions rather than formal organised structures like the UK model, which makes party discipline weaker and a coherent approach to policy weaker AO1: Parties in the US and the UK have organised leadership within Parliament/Congress to organise party business and facilitate support for/in opposition to prime ministerial/presidential agendas AO2: US parties tend to only meet nationally at national party conventions - which are more about choosing presidential candidates than formulating policy AO1: Partisanship has grown in the US in recent years to more closely resemble the UK model in voting patterns in Congress AO2: Within both the UK and the US individuals are becoming more outspoken and acting ‘outside’ the party line, particularly on divisive issues, e.g. Jacob Rees-Mogg in the UK AO1: Rational theory: AO2: Factions appear and disappear in relation to changes in society AO1: Factions can also affect parties’ chances of formulating coordinated responses to key issues and policies, e.g. AO2: Momentum has deeply divided the modern Labour Party AO1: Unity can also depend on key individuals within the party AO2: This can also affect the role of individuals in parties if factions coalesce around key individuals who are divisive AO1: Structural theory: AO2: Layout of Parliament and organisation of parliamentary business encourages party coordination and unity in the UK AO1: US Constitution and system of federalism discourages/prevents effective party unity AO2: Cultural theory: AO1: UK historically has focused on parties; parties coordinate more closely on manifestoes and campaigning than in the US AO2: US society tends to focus on individuals rather than parties; lack national manifestoes and coordinated policy agendas