explain the difference between federal and unitary states with reference to the UK constitution. Analyze the development of the law governing devolution to some of the UK nations.

In light of the way devolution to the UK nations has developed since 1998, the UK can no longer sustain being a unitary state and should become a federal state.

Critically evaluate this statement in light of the legal development of national devolution within the UK.
The essay requires you to:
Concisely explain the difference between federal and unitary states with reference to the UK constitution.
Analyze the development of the law governing devolution to some of the UK nations (discussing at least two of Scotland, Wales and Northern Ireland)
Evaluate whether the UK would be able to be more effectively governed as a federal state, in light of your analysis
throughout the entire essay, develop a balanced argument that will either agree or disagree with the statement, addressing relevant counter-arguments.