Consider the following FARs,
§ 91.126 Operating on or in the vicinity of an airport in Class G
airspace.
b) Direction of turns. When approaching to land at an airport without
an operating control tower in Class G airspace-
(1) Each pilot of an airplane must make all turns of that airplane to
the left ....

AND
91.129 Operations in Class D airspace.
(a) General. ... each person operating an aircraft in Class D airspace
must comply with ... §§91.126 and 91.127.

The question could be asked, how do you join the pattern, since when
attempting same you are obviously "approaching to land at an airport"

Now, AIM 4-3-3. Traffic Patterns Provides some recommendations:

http://www.faa.gov/atpubs/aim/Chap4/4-3-1

with "(See FIG 4-3-2)".

Now interestingly, this figure shows a 45 degree right turn to join
the downwind, with the example stating:
"Enter pattern in level flight, abeam the midpoint of the runway."

However, and this is the quandary, the AIM example recommends a
procedure that seems to be against the FAR about left turns when
"approaching to land".

Can it be that joining the pattern is not considered as "approaching
to land", and hence, mandatory left turns are not required?

Because if so, a pilot can be on a RIGHT base, thus join the circuit
turning to final, and thus avoid the whole idea of a left traffic
pattern, and the "all turns to the left when approaching to land" FAR.

Loopholes, anyone?

Stan