Are tags applicable to every resource request in my html or only in my index.html?
Just the HTML document itself, theoretically, if even that.
HTML 5 does not mention cache control headers for a list of specific http-equiv values.
The wiki extension has this to say about cache:
; HTTP-.
XHR?
.
mnot:
- , arent . , theyre , - ( HTML ). Pragma: no-cache -, .
HTTP-. , ( ), .