How and why do the two main American political parties differ?

One of the most notable features of the political landscape in the US is the complete dominance of the Republican and Democratic parties, insofar as these organisations have, since the Civil War, been the channels from which Presidents and almost all national legislators are drawn. The barriers that exist to attempts by third parties to expand the party structure are such that only the most well funded and well managed can even hope to make any inroads; single-issue groups inevitably find their stance undermined by an absorption of their position by one of the two major parties. Only the Socialist Party around the First World War and latterly Ross Perot's Independents are worthy of mention in this regard. The former proved to be a transitory and short-lived body; it remains to be seen whether the latter will follow in its path. Thus is reflected the strength of the bipartisan system; yet this is not a system with one party of the free-market, capitalist right and another of the Keynesian socialist left as in other countries. Broad areas of consensus exist on the market economy, foreign policy, and the constitution; some outsiders see such agreement as occasion to ridicule the two parties as clones, whose ideology and policy outlooks are so homogenous that rhetoric and appearance at the party conventions are the only way to sway voters. This is, however, fallacious; there are significant divergences between the parties on questions of ideological foundation, organisation, cohesion, self-esteem, and attitudes to dissent. All of these areas must be examined to fully understand the nature and implications of the differences between the two parties.
According to Freeman, there are two fundamental differences between the parties that are the sources of all others; firstly, the nature of the distribution of power in the parties: in the Republican party, power flows from the top down, whereas the opposite is true in the Democratic party. Secondly, their attitudes to themselves with regard to holding office differ; the Republicans, in much the same way as the Conservative party in Britain, see themselves as the natural party of power, and regard themselves as insiders even when out of power. By contrast, the Democrats are very much outsiders, even when they do hold power. These key features explain the great differences in the way in which the internal politics of the parties are conducted, regardless of the final policies adopted and their implementation that, as Freeman rightly points out, must pass through the "fiber [sic.] of political reality;" i.e. both parties face the same institutional restrictions on policy implementation when in power. It is in the process of debate, discussion, and deciding of policies that distinguishes the parties most from one another.
This is reflected in the Republican party by the deference that is demanded of the activists to their leaders; those subordinate to the leadership are required to be "good soldiers." The downward flow of power as described above makes groups that form beneath the leaders dangerous, and are potential foci for disloyalty and dissent. Thus there is an air of authoritarianism that pervades the Republican party and its structure; by contrast to this, the upward-flowing power in the Democratic party cannot exist without coherent and distinct groupings that provide initiative and insight to the leadership and act collectively to develop and implement the party's agenda; thus there are multiple power centres to the Democratic party, based around the organised groups that are the most important components of the party, namely organised labour, black and Asian groups, and women's activists. The purpose of these groups is to channel outside sentiment into the party and provide conduits for opinion to reach those who will ultimately decide the direction and policies of the party. The Republican party also has component groups, but they are ideological and geographical factions, as opposed to pressure groups; their importance is much less than to the Democrats. In the Republican's case, they are not mechanisms for exerting power or sounding opinion; instead, they exist to carry the party's message outwards to the voters, and are internal party organisations, rather then independent bodies that are affiliated to or work primarily for the party. There are resultant differences in the manner in which change occurs in the parties; the Democrats, being driven primarily by interest and pressure groups, are much more responsive to reforms from within, a fact that stems from the 1968 convention in Chicago, where the party's divisions became clear for all to see. Thus change is a relatively gradual and ongoing process for them. In order for a group to be successful within the Democratic party, it is important that what it represents remains salient and important to the nation or a great proportion of it. The Republicans respond more readily to changes in leadership, and success depends on ties an individual has to a successful leader or group; mavericks and independents can rarely build a power base within the party. The discontinuities that sudden changes in leadership produce result in the process of change for the Republicans being sudden and sometimes involving the opening up of fissures within the party over an issue, although core values are rarely affected in this way.
The second source of differences between the parties is reflected in their attitude towards the state; the Republicans represent themselves as struggling to prevent the domination of the state over the individual; they see the state as a threat to their power. They firmly believe that what they are and their conception of the "American Dream" is inherently desirable. They are the insiders who represent the core of American society and its values, and look after the national interest, rather than the Democrats, who simply look after the interests of the powerful groups within that party. This insiders' view regards their achievement of power as being the result of hard work and merit; means that should be used by all to achieve their goals. Individual success should be encouraged, and the best way to improve the welfare of minorities is through economic improvement. An opposite view is held by the Democrats, especially in regard to the role of government, which is seen as a necessary check to the domination of private economic interests. However, there also exists a certain amount of ambivalence towards the state on the part of the Democrats, who are unsure as to how far it should intervene in promoting the economic welfare of minorities, and how it should incorporate representation of the viewpoints of all relative groups. There are also potential conflicts between the groups composing the bulk of the Democratic party over what is a fair distribution of income, and how that should be achieved; consequently, there is little discussion of this in public. Having said that, however, the organisation style of the Democratic party is such that the conduct of internal party politics is open, loud, and confrontational. Speaking out in such a manner is not seen as degrading the party's standing in the electorate's eyes, however, but rather a means of access; very often, winning recognition for a particular grouping is often more important to it than winning the issue. Many of these arguments are based around changing (often declining) influences within the party. By comparison, Republican business is conducted quietly, behind closed doors, and in a consensual manner. It is thus rare to see Republicans openly confront or criticise each other in public. Both these approaches to resolving divisions have their advantages and disadvantages. Republican differences are seen less in public, and thus it is easier to maintain an image of unity at election time. On the other hand, feuds within the party can run deeper and last longer than the open disagreements seen in the Democratic party, who have a tendency to make up more quickly after arguments. These characteristics can again be traced to the nature of the Democrats as a broad coalition, and the Republicans as a unitary organisation. In the case of the former, as discussion is required on each new idea in order to reach a consensus, their approach tends to be more stable in the long-term once this consensus has formed. Ware believes that the current divisions in the Republican party over moral issues such as abortion may hamper the party's long-term Presidential fortunes, as any potential nominee would have to build enough support among the conservative South where, although not enjoying the hegemony that the Democrats were until recently used to, they are in the ascendancy, whilst at the same time appealing to moderates in the North-East. This view is consistent with Freeman's view on the nature of the potential longevity of splits within the party, but was written before the start of the decline of the Clinton presidency, which provides extenuating circumstances in which this theory might not be realised. The next Presidential election will undoubtedly be fought against the backdrop of the fallout of Clinton's impeachment trial, which will provide little opportunity to examine questions of splits over moral issues in the Republican party.
Finally, it is apparent that there are differences in the forces of cohesion that play on the two parties. Although united by a desire to win elections, and especially having their man in the White House, different factors act as incentives for unity to the different parties. For the Republicans, it is the narrow social base that they are drawn from, with the majority representing the stereotypical North-Eastern WASP demographic cross-section. They are on the whole a socially homogenous grouping from similar social strata; such a grouping allows trust to arise easily among them. The Democrats are a much more heterogenous group, with inputs from many different social and ethnic groups. This can give rise to misunderstanding, but at the same time, it is this pluralism that holds the Democrats together.
Thus it is clear that whilst there may not be great differences in the eventual policy agendas that the two parties adopt in the run-up to elections, the way in which they are arrived at is significantly different. In fact, it could even be said that the parties are in many ways mirror images of each other: the Republicans the righteous, dedicated, and respectful authoritarians, and the Democrats the inclusive and discursive pluralists. Yet both are flexible and malleable entities, which explains their success over the years; as long as they both remain committed to maintaining a two-party system, then they will be able to do so, regardless of the differences between them.