Nukes are not the solution to your problems

It has been said that Nuclear weapons are the "greatest peacekeeping invention" in history- but will it really last? Sure, it may have stopped war around WWII times, but today isn;t the same. Numerous countries now are in possession of nuclear warheads- an estimated 19,000 of them it seems- and America, Pakistan, and Israel being of the more famous owners of them.
But why do they have nukes in the first place? Common reasons range from, as above, keeping peace to having defense against others who have them. Defending against weapons. The original plan for them is no longer valid since we don't need to go bombarding japan every few years.
First off, keeping them to defend against more nuclear weapons is already flawed logic. A large reason why other ocuntries are assembling warheads at all is to combat their foes and their nuclear weapons. Such as the USA. The american government has nuclear weapons to combat foreign ones, which were, sometimes, spurred by us. It becomes simple, if all sides put down their arms then there is no need to raise them back up.
Of course there could always be an insurrection where having some force could help. If a World War III started, then perhaps nuking another country would solve it for sure. To me that sounds absurd; solving violence with more violence. Not to mention the thousands of innocents nukes take off by default. They can't cloose which part of the country- what house to muke. It's a weapon of mass destruction for a reason.
But why bombard another country to solve a war? Will that work like WWII? i'm sure it won't. Say, we got in a war with pakistan or which ever country you like with warheads. If we bombard them, they'll respond with theirs. That's what they make them for. defending against stuff like that.
It won't be like Japan where they surrender wthout a fight- and it won't end well.
Naturally you could say that countries realize this, so they won't attack another, therby creating some strange form of peace and nonwar. However that's a risk. A gamble of no countries doing anything dumb and not all people are of the same views as another- it makes us what we are. Human.
The USA might one day find a cause to engage war in, maybe the europeans will want us out of their land, maybe a terrorist group will get some for their own usage and that could mean anything really. Following any of these or however you want to make up, it will not only end in probable casualties of who knows how many, but loads of other complications as well..