I really would like to know what kind of counter measures or AD measures it has should its jets fail to do their job ( highly unlikely I geuss ).

What ship?, HMS Ocean?.

And is it possible to breach the defensive bubble of a advanced ( US ) carrier ?

Yes, if you can overwhelm its defences with weapons and countermeasures, it wouldn’t be easy though.

Missed opportunity- HMS OCEAN

I think HMS Ocean should have been designed as a Invincible class replacement rather than a one off LPH.

Rather than expensive refits to improve the Invincible’s aviation capabilities, the RN could have started operating its Harriers off a much improved design and relegated the Invincible’s to LPH duties until enough improved Ocean’s had entered service.

The Ocean class should have been 30kt capable, ski-jump equipped, 25,000t light carriers operating 25 aircraft. It should have been a improvement on the Invincible’s in every way, cheaper to build, more affordable to operate, easier to crew, have a better layout (flightdeck, hanger, accessibility, weapons) and it should have been built in greater numbers (4+ ships).

Well I know one country that doesn’t need their carrier, Thailand, during the Tsunami crisis she just sat there tied up alongside. The whole reason they bought her was for disaster relief so they claimed, we when a disaster came, she wasn’t there, so they should sell her off, there are a few countries that could use her and would be willing to pay a good price for her.

HTMS Chakri Naruebet always did seem to be more of a status symbol than a useful asset, I don’t know why they bothered with the AV-8As, they should have spent the money on helicopters.

I think the usage of the word need is wrong, want is probably more appropriate, a carrier as with most other military force today is about what the countrys rolein the world is, If north korea wanted a similar role to the USA,it would arguably need an aircraft carrier.

Good point, I think most countries ‘want’ them but can’t justify the need or expense for them.

I will edit the question to want/need.