There is an interesting article in this week's Economist magazine that suggests that Israel's parliamentary system of proportional representation may in fact be a contributing factor to the long-running deadlock (or deterioration) in Israeli-Palestinian political relations.  

That is to say, the system of proportional representation used for electing the Israeli parliament leads to a  multiplicity of political parties, many with only a few seats and representing only a small and specialized minority group.  This in turn results in an endless series of impossibly complex coalition governments.  Israel is not unlike Italy or Belgium in this respect.

This seems like an interesting topic for discussion, not so much the Israeli-Palestine angle, but rather the fact that any given electoral structure, used in any given jurisdiction, can facilitate or hinder particular policy options or results.

Is anyone interested in this topic?  

I suppose what I'm really discussing here is the relative merits of electoral voting systems between 'plurality' (aka 'first past the post') or 'proportional representation' systems.  Either one can be used with either parliamentary or congressional systems of legislature, so the question is, which one is better?  

Technically speaking, the same trend is evident in every western country.  If you follow birth-rate projections, then 'christians' could easily become minorities in many western nations in 50 or 100 years from now.

I understand the topic here to be 'electoral systems' not Israel.

But the trend in EVERY country that uses proportional representation systems is to increase the number (and decrease the average size) of political parties.

This is what I'd call a 'structural' effect of this policy choice.

With respect to the 'plurality' system (used in USA, Canada & UK), the evidence is mixed about parties - the number of parties has dropped in US & UK, but increased slightly in Canada.  Ergo, there is no evidence that the 'plurality' system has a structural bias for two-party or for growing more parties. 

I don't know what is 'necessary' or not.

The fact is, that is the trend in countries with proportional representation systems.  Over time, the number of parties in the legislature increases as the average size of the parties shrinks in size (increasing numbers of smaller parties).

This is a relatively 'new' phenomenum - fact is, proportional representation is a fairly 'new' model and has only been applied since WW2.  One can't know all the 'unintended' effects of any given structural policy until it is applied.

That's one of the strong points for the 'pluralist' system used in the UK, USA and Canada - it is hundreds of years old, and thus, most of its systemic effects, be they beneficial or detrimental, are widely known already.  With PR, new 'effects' are becoming apparent over time that were not present in the original model that was widely praised (and applied in quite a few countries).

I think Israel, Italy and Belgium are showing the most advanced problems with PR systems in the present day.