A federal government is less effective in the spheres of foreign policy and national defence as compared to a unitary government. The component units may place impediments in the way of the central government in carrying out its treaty obligations with other states.
It is inefficient as compared to a unitary government because of diversity of law and administration obtaining in the country.
2. Clash between National and Local Interests:
There is always a tug-of-war going on between local and national interests. Sometimes one is sacrificed for the sake of the other. This struggle is detrimental to the best interests of the country.
3. Highly Expensive:
A federation is a highly expensive government because there is duplication of all political institutions.