Economically, the wizard's economy depends entirely on goblins, so the Ministry of Magic is completely incapable of supporting a war. Muggle society has a complete financial system. At the same time, many things of wizards are not complete. Many lives need the help of Muggle society to be completed. Wizards have the advantage of magic and magical animals. But magical animals may not even help wizards. And magic is almost useless in war, especially in modern war.
Let's take a look at Lindevo, the personality who supports the wizard to rule Muggles. He is proficient in magic, but he still wants to use the power of the deathly Hallows. He put forward the slogan "for greater benefit" to attract believers. But in the wizard's eyes, he is a complete dictator. Of course, you can say that Voldemort made many terrorist attacks in Britain. However, the prime minister is more concerned about whether his political opponents can come to power than whether the country is complete. Just like terrorists can make waves, but not for long. Wizards may not win the Muggle War.
I am so powerful that I won't hide like a street mouse. Harry Potter is not really a high magic world. Once exposed and set on fire by muggles, it will be abolished. They all make soap for their fellow human beings, and they all want to make others angry and make others bad, not to mention different wizards who have been stigmatized. Moreover, it was on the eve of the war, and it was easy for an unknown civilization to suddenly appear, leading to panic and further slaughter. So the Ministry of Magic was right. If you can really beat your bully, who will turn? what do you think?