The conclusion is obviously impossible. Just look at the debt crisis that is currently causing Europe to suffer. Moreover, the international currency status of the U.S. dollar cannot be easily shaken by any currency. This can also be seen from the current bottom-dipping exchange rate of the euro against the U.S. dollar and the foreign exchange holding structure of the Central Bank of China.

The following is the text:

The so-called "optimal currency area" means that countries in a region have a common currency after complete currency integration, or maintain the currency of each country. A rigid fixed exchange rate system and complete currency convertibility, while floating exchange rates outside the region. The core of "optimum" is the ability to protect external equilibrium and achieve full employment and price stability; "optimum currency" refers to a fixed exchange rate currency or unified currency that replaces floating exchange rates; "optimum currency area" emphasizes A relatively stable currency area constructed within a certain area in an effort to achieve internal and external balance relative to the entire turbulent international financial system.

The main conditions that constitute the "optimal currency area":

1. High mobility of production factors.

2. Economic openness is relatively high.

3. Diversification of product production.

4. Similarity of inflation.

5. The degree of policy integration is relatively high.

Compared with these five conditions, the emergence of the Eurozone can be said to be quite a piece of cake.

First of all, the biggest weakness of the Eurozone is that each region cannot implement independent monetary policies.

The "optimal currency area" is not the real "optimal" currency area, because not only does it not get rid of the fetters of what Krugman calls the "Eternal Triangle" (Eternal Triangle), but it is "eternal" A manifestation of "triangle". Under the "triple paradox" that "exchange rate stability, free capital flow, and monetary policy independence" are incompatible, the "optimal currency area" has intertwined interests and sacrifices for "exchange rate stability, free capital flow" The result of “monetary policy independence”. There is a danger here, that is, the member states choose the "optimal currency area" due to the intersection of interests, or it may still be based on the changed interests, leading to the disintegration of the "optimal currency area".

Obviously, the EU is now in a huge contradiction between monetary policy independence and exchange rate stability. On the one hand, countries such as Greece and Spain that rushed to join the Eurozone did not comply with the provisions of the Maastricht Treaty at that time, which led to the ongoing debt crises in southern Europe. On the other hand, a unified currency prevents these relatively economically weak countries from being able to flexibly use monetary means such as lowering exchange rates to alleviate domestic crises and extremely high financing costs. This is undoubtedly a major factor in the long-lasting European debt crisis.

Secondly, the independent fiscal policies of European countries also prevent the European Central Bank from effectively using unified fiscal policies for regulation when a crisis occurs.

Thirdly, Europe still has quite a few differences both in language and traditional culture. It can be seen from the industrious and rigorous Germans' unwillingness to assist the free and undisciplined Greeks. This cultural understanding makes it difficult for them to carry out free movement of labor within a large area like the United States.

Fourth, the diversification of products in European countries is not very ideal. Various countries do not have that much need for division of labor and cooperation in production.

Finally, with the deepening of the European integration process, it can be said that there are fewer and fewer trade barriers between European countries. But compared to the United States, a unified and independent federal country, the EU's trade-only trade still has a long way to go. The different interest demands of various countries will certainly not make the trade barriers between European countries disappear as invisible as one country.

To sum up, not to mention that the euro surpassed the US dollar in a short period of time, it is also lucky for the euro that it can survive the current economic crisis.

In fact, the emergence of the euro is a political need.

p.s. The poster’s share is quite reasonable, haha