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Assume that ww1 somehow was prevented in 1914 and by 1917-1920 the situation become similar to a Cold War.

What would British politics look like? Also how would their economy perform?

My views:

First, for sure Irish question and Land Reform would be the two main topics. The Liberal Party would be a major force for longer, especially if Home Rule was passed and Ireland was resolved peacefully, while Georgist policy of LVT would undermine both the right and the far left.

For economy, of course the macroeconomy would be much better: low debt, low deficit, net creditor. A national LVT can have positive impacts on economic development in the long run.

However, the laissez faire oriented economic policy would prevail for much longer, as ww1 created the conditions of the emergence of Keynesian economics and state interventionism. Potential negative effects: slower technological advance, slower to adopt assembly lines and mechanization in manufacturing, worse infrastructures, disorganized electricity supply system (as far as I know, there was absolutely no government plan for a standardized national electricity system like Central Electricity Board BEFORE WW1), disorganized railways.
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