Israel

A constitution is formalization of a set of societal/cultural principles and ideals that the country should strive to achieve.

Bah. US culture has changed so much that parts of the constitution aren't even being taken in context any more. Take the fifth amendment, for example. It applies until you're read the Miranda, and then anything you say or do is treated as deliberate and willing self-incrimination, even when you're being beaten down psychologically – completely opposite to the intention of those who wrote the constitution.

That's because the ideals in the US constitution were the ideals of a group who, while having the right idea, were pretty out of touch; virtually nobody was paying attention to the Fifth Amendment until Miranda.

So realistically, you're only going to be able to keep the principles written in your constitution if your country's culture supports them. And if it does, what's the point in writing those principles down? If they're written down, people'll start following the letter and not the spirit.

The principle behind English Common Law is to write down the laws people are already following. That principle keeps you from getting all dictatorial, but only if the culture allows it (by enforcing it). (I'm concerned that that's becoming less of the case, but that's off-topic.) That's why Britain doesn't really have a constitution; the Magna Carta is the closest thing, but that's completely moot until the government gets so corrupt that the monarch throws it away and starts again with a new government.