“If we had Chavez’s back to the wall, and a cruise ship with a couple of thousand US citizens on it got blown up, would we be able to prove who did it?”
That’s a real stretch. Do you really believe we can’t track every move of a diesel powered submarine? Are they any match for a nuclear-powered U.S. hunter-killer?
The TOTAL US attack submarine fleet is 47 Los Angeles-class, 3 Seawolf class, and 4 Virginia class -- a total of 54 subs
Do we have the resources to be tracking every diesel sub in the world? Chavez is getting his diesels for $250M each. A Virginia-class nuke sub is $2.3B.
Now add in China's buildup, Iran, North Korea, and we may find ourselves unable to find the money to keep enough of our fancy subs at sea to be able to track everything our enemies can send out
In the right hands? No, we can't. The Swedes have had a diesel boat at San Diego for over a year now and it runs rings around every U.S. nuke sent to find it.
Having said that, submarines take a trained crew to run. Venezuela has two 30 year old German diesel boats, and I'd have to wonder how effective they've been for the last decade or more. So it stands to reason that Venzuela has few trained submariners to man these boats with. And fewer, if any, submarine commanders who can make the most of their capabilities.