"Conventional weapons are destructive enough"

No, they really aren't. Israel has been peppered with hundreds of rockets on the time frame of days or weeks, and at the national scale, they were basically an inconvenience. One nuke, by contrast, can take out an entire city. North Korea currently has at best the capacity to really badly hurt South Korea before they were rendered militarily ineffective, and even then, for all the death and destruction they could cause, most of Seoul would still be there afterwards. If they have nukes, though, most of Seoul could be destroyed in one fell swoop. Or most of anything they can reach, which also includes an awful lot of China.

It turns out that if you plot the destructive radius of even very large nuclear bombs, many cities are actually substantially larger than just one. But, still, between fallout concerns and the fact that there is now a total hole in your city's infrastructure, one nuke is still probably enough to kill an entire city, if not necessarily every person in it. There aren't any conventional weapons we can say that about.

There also aren't any chemical weapons we can say that about. Their effects are very mean and very nasty and very hideous, but they're also a great deal more limited than the common conception of them. For instance, one of the characteristics that makes mustard gas appealing is that it's heavier than air, which means that it tends to collect in below-ground-level fortifications, forcing the enemy out. This same characteristic renders it useless for destroying a city.

As for biological weapons, well, we do tend to speak of them in the same breath as nuclear weapons. However, their big problem is that it's difficult to create a really effective one that is also guaranteed not to kill the user. You've basically got the choice of things like smallpox, which are effective and contagious but you won't be able to stop hitting you (if nothing else, your enemy may well consider medieval warfare a source of inspiration and just start dropping infected bodies on you), or you have things like anthrax which are effective, but being not particularly contagious means that it's actually quite difficult to get them into people at scale.

Even now, nukes are a problem.

To my knowledge rockets fired at Israel are very basic, while Israel has the Iron Dome in place, thus it is a bit of cherry picking. Conventional bombs can surely destroy cities. Nevertheless, an argument can be made nuclear bombs are more cost effective, I don't know about that.

Chemical weapons are certainly WMDs and very potent, as seen in the Syria attacks.

There are many ways you can hurt your enemy, depending on one's goals. E.g. as far as I remember the central element of Mr. Robot is an attack on world economy, which might cause more disruption and suffering than killing civilians.

Reflecting back on history, we don't even have many nuclear incidents. On the other hand it shows if we are serious about hurting others we will find a way.

Also, just for thoughts, if we leave the western centric pov, every other nation could be concerned with the west having nuclear capabilities while they are denied.

> To my knowledge rockets fired at Israel are very basic, while Israel has the Iron Dome in place, thus it is a bit of cherry picking.

My understanding is that most of the rockets fired at Israel are not loaded with explosives, and that most of the damage comes from whatever fuel is left when they impact.

Mass surveillance hasnot been effective yet.

despite some recent high profile terrorist act in Europe or the numerous shootings in the US which are used to push this agenda.

While just the other day, people on this very same site were freaking out because they clicked a button that populated their search history with some questionable items.