There were many reasons for not unifying in one
political system:<span>
One of them was the geography, Greece contained many mountainous
terrains, valleys which were separated from each other, many islands where it
was easy to form new towns and settlement, giving birth to many power centers
instead of one
Another reason was the sense of heroism in Greece and to
fulfil that the great Mediterranean, they could sail to wherever they wanted in
the times of need resulting from any kind of crisis and this helped them
establish new colonies all over the Mediterranean.
<span>Third reason was the presence of aristocracy who denied the
establishment of a monarch and each city or state defended their independence.</span></span>
The Persian empire was an imperial dynasty in the period 550-330 BC centered in Iran (known in that time as Persia.) I<span>t spanned from northern Greece,through Turkey, Syria, Lebanon, Israel and Palestine, Iran, Iraq, Kuwait, Egypt, parts of Lybia and Sudan, Afghanistan, Pakistan...
</span>The modern country Egypt is an example for a country that was part of the Persian empire.
Checks and balances are controls built into our system of government which prevents one branch of government from asserting too much power over the others. For instance, the President may want to declare war, but he must first seek the approval of Congress.
The resulting outcry across the United States led to a number of antiwar demonstrations—it was at one of these demonstrations that the National Guard shot four protesters at Kent State.
There are many possible answers for this one! Only the national government can e.g. manage foreign relations, declare war or oversee trade between states and with other countries.
