How were nations like Spain, Italy, and Germany able to overcome tribal and clan conflicts over the centuries to become united countries? CHECK ALL THAT APPLY

A. A national religion was declared
B. Nationalist leaders emphasized the thing the tribes had in common
C. The most powerful clans killed off the weaker ones
D. Other countries invaded them and forced them to cooperate

B. Nationalist leaders emphasized the things the tribes had in common

Explanation:

Internal conflicts between tribes and clans in a country can weaken the country's power very severely. These conflicts remove the country's unity and weaken its sovereignty, thus making it easier for an enemy nation to seize and dominate a disunited nation full of internal conflicts. Nations such as Spain, Germany and Italy have faced many problems with conflicts between clans and tribes and suffered severe consequences. However, the emergence of nationalist leaders, concerned with the sovereignty of the country, sought ways to show the points that tribes and clans had in common, and showed that a strong nation was a united nation.

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