Step 1: Define communalism.
Communalism is the belief that people belonging to a particular religion form a single, unified community whose interests are separate from and often opposed to people of other religions, used to justify treating religious groups as rival political blocs.
Step 2: Explain historical and political causes.
Colonial policies that classified and sometimes favoured communities separately deepened religious divisions, and after independence, political parties have at times used religious identity to gather votes, which keeps communal thinking alive for electoral gain.
Step 3: Explain social and economic causes.
Competition over jobs, land, or resources between communities can be reframed as a religious conflict rather than an economic one, and rumours or provocative propaganda, spread quickly today through social media, can turn small incidents into large scale communal tension.
Step 4: Explain the consequences.
Communalism can lead to riots and loss of life and property, it damages social trust and daily cooperation between communities living side by side, it can result in ghettoisation where communities cluster separately out of fear, and it weakens the secular, inclusive character of Indian democracy.
Final Answer:
Communalism treats religion as the basis of rival community interests; it grows from historical, political, and economic causes and leads to violence, mistrust, and weakened social unity.