World War III: what are your thoughts on cybercrime/cyberwarfare and has WWIII already started without the headlines?

Whether or not we are in WWIII remains to be seen though it does seem feasable. However, I will say this, we are a country of weak Cyber Defense. In terms of security you have to know both sides to truly be successful at defense and if you don't know how to break into something how can you honestly say you can properly secure it if you don't know what to look for. I do not think we are at a point yet where we could secure our systems in such a way that will stop the likes of China or Russia. Nor do I think we have the personnel truly capable of launching an attack the likes of which China and Russia can.

Adding to what PO2 Ed C. stated, defense makes the best offense. It's not enough to simply hide behind authentication methods. If you know nothing about man in the middle, disgruntled users, safe internet browsing, or safeguarding your data, you're way behind the power curve.

I think WWIII started some time ago, but we have been reluctant to get involved in a serious way. We are currently in the Neville Chamberlain phase.

Well for starters WWIII has not started yet although it seems the Hermit Kingdom's "leader" seems to be doing his best to initiate it CPO Tim Dickey.
We are still engaged in a cold war with Russia and Iran even while we are building up forces and capabilities in eastern Europe and northern Iraq which birders on Iran.
Cyberwarfare has been going on for decades, much of what we are dealing with is hacking and extraction of data from our more vulnerable systems. Thankfully we have been successfully attacked by anything like the Stuxnet virus which crippled a significant amount of Iran's nuclear capabilities. Let's hope that our defences of the systems that matter the most are robust and defended in depth.