Under what conditions can the mercantilist model (Germany's current model, for example) be effective?

The mercantilist model is that used by countries where growth is generated by exports and where a significant share of income is generated by the revenues linked to the accumulation of external assets. Under what conditions can the mercantilist model (which is used by Germany currently) be effective? There must be free trade and a lack of protectionism; There must be no requirement that production shall be close to the end-buyers of goods; The country's competitiveness (which results from the level of product sophistication, the exchange rate and costs) must be strong.