US Nuclear Weapon Sharing Under AUKUS? Addition.

The US program of sharing a few nuclear weapons with some Western European countries (and with Turkey) is a more sensitive subject of corridor discussions under AUKUS.

The Western European/Turkish nuclear delivery platforms are joint strike fighters (eg. F-16s increasingly F-35As) armed with "dial-a-yield" B61 nuclear free-fall bombs. "In case of war, the United States has told NATO allies the Non-Proliferation Treaty (NPT) would no longer be in effect".

Any sharing with Australia would need to involve much longer range delivery platforms eg. costly B-21 very long range bombers if sold to Australia (possible publicity 2023 as anti-shipping strike aircraft), possibly Aus and US developed ICBMs by (say) 2033, and future Aus SSNs that could be hypersonic cruise missile capable (2040s). 

Regarding SSN platforms 4 or perhaps 12 (3 per Virginia Payload Tube (VPT)) vertically launched hypersonic missiles, called Long-Range Hypersonic Weapons (LRHWs), could be carried on each SSN. LRHWs, with a range of 3,000km, may be deployed by the US Army as early as 2023 and on USN Virginia SSNs by the late 2020s. UK SSN(R)s, maybe available in the 2040s, might also be armed with 4 VPTs (hence 12 hypersonic missiles). 

Back to Western Europe/Turkey regarding longer range delivery platforms :

"Historically, the shared nuclear weapon delivery systems were not restricted to bombs. Greece used Nike-Hercules Missiles....PGM-19 Jupiter medium-range ballistic missiles were shared with Italian air force units and Turkish units with U.S. dual key systems to enable the warheads.[9] PGM-17 Thor intermediate-range ballistic missiles were forward deployed to the UK with RAF crews."

Joint UK-Australia Nuclear and Missile Tests

In 1946 the Aus-UK Joint Weapons Project was formed, based around the establishment of a long-range weapons testing facility at Woomera (see maps above). Subsequently IRBM tests in/from Woomera and Aus-UK nuclear weapon tests were conducted at Maralinga within Woomera. Woomera remains the largest land-based test range in the Western world and has the second highest number of rocket launches internationally after Cape Canaveral.

Back to US-Australia

The beauty of Aus ICBMs is that US personnel (with one of the keys' authority) could be joint based. The location of a 100? hardened silo missile area would ideally be in central Australia (to give the longest launch on warning decision period). If it had to be based south of the most central location then the northern portion of the 122,188 km2 RAAF Woomera Range (aka Prohibited Areas) Complex (see maps above) long defence land might be acceptable. 

There could be a AUS-US dual key/code system to enable the ICBM warheads. Also a AUS-US dual key/code system to arm Aus B-21 bombs/ASMs and the SSNs' hypersonic SLCMs may be practical. 

Chinese submarines, with hypersonic/ballistic missiles, in coastal waters south of Woomera would be the greatest threat to Aus and?or US ICBMs in their silos. The seabed sensor system emplaced for many years around Australia would need to be further upgraded and weaponised (including smart sea mines), to counter this Chinese threat. Otherwise the Aus ICBM second strike decision period, and rush to get Aus B-21s in the air, would be highly compressed.  

Australia Needs Nuclear Weapons One Way or Another

To face the China threat (particularly post-Taiwan takeover) Australia will need to develop its own nuclear weapons, with non-US or non-UK help, if required, eg. help from Israel? This is if:

-  the US (or maybe UK) refuse to share nuclear weapons with Australia

- this is especially if the US decides it cannot sell Virginias to Australia

and

-  if the UK only has the SSN(R) option: meaning UK-Aus SSNs available too late, in the 2040s-2050s. 

However Woomera could contain a permanent High Level Radioactive Waste dump noting Australian Defence Minister Mares is talking about such a dump to be on current or future Defence land. Not only Australian waste but perhaps US and UK waste could use it. This concept might have already been floated under classified (very non-public) AUKUS agreements. Such waste access might constitute a major barter item for Australia to build a nuclear weapon capability under US "shelter".