Nuclear Hypocrites

I'm watching with interest this present brinkmanship between Iran and US/Europe over Iran's possible intention to manufacture nuclear weapons. It is entirely possible they could build nuclear weapons over some years but how does that effect global security?.
USA,Israel,Russia,China, N Korea,UK,India amongst others have varying amounts of Nuclear warheads.

Most countries (Notably USA and European countries) have signed up to the Nuclear nonproliferation pact. This accord was primarily to reduce nuclear weapons at an agreed rate at the end of the cold war and stop the manufacture of any new nukes.
unfortunately once the USSR broke up nobody seemed to have any inclination to reduce their stockpiles and as has transpired the USA and UK are developing replacement nukes for the rapidly aging trident missiles. This to me (and the 'Times') is a material breach of the accord and certainly not in the spirirt of the treaty.

So here we go preaching to nations to not build them (or face our wrath in sactions or worse) yet are quite happily sitting on our own for no legitimate reason. We are quite happy to 'let countries off' when we find they have secretly developed them (Israel,India, Pakistan) and then be their best mates and sell them more convential weapons such as f18's etc in the case of the USA to India recently.

This whole nuclear situation is poop and it's time this treaty was actually upheld before other countries are invaded 'just in case' they might be thinking of making them. We 'shouldn't throw stones if we live in glass houses' and we are a shocking example of hypocrisy in this instance. What does the UK think we can achieve with our warheads anyway. We are hardly going to nuke China or Russia with 20 odd tridents all of which are so old they probably would fail to launch. Is it that the countries with large stockiles simply cannot afford economically to safely dismantle them.

Maybe we could all do like the USA and fire our nuclear waste at our enemies (Depleted Uranium warheads anyone?). Iran might like the fuel......................