1. What does GDP measure?
Tax base.

2. Why does it need to grow?
To enable politicians to keep their promises, wheter in expanding services but not increasing taxes or lowering tax percentages while keeping services constant. Or both. Few run on a platform of increased taxes and lowered services. Or on a reality-based platform where you need to pay for what you eat. Fiscal conservative is just a oppostion position, when in power you need to keep promises.

3. Does the need for GDP growth outweigh any other policy goal?
Policy is set by politicians right? Then - almost always - yes.

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