In terms of resources, you must consider that you are not only
pitting NK against the Yanks, but SK as well.
USA made some moves in March 2003 to warn North Korea not to
make rash moves.
On March 19 2003, it launched joint war games with South
Korea to send a message to the North.
South Korea,
March 19 (UPI) -- The United States and South Korea kicked
off another set of major joint military exercises Wednesday aimed
at deterring threats from North Korea.
The 8-day, computer-based command training drill, code-named
Reception, Staging, Onward Movement and Integration, coincided with
ongoing monthlong joint field exercises of Foal Eagle that
run through April 2.
http://nucnews.net/nucnews/2003nn/0303nn/030319nn.htm#035
The next day, March 20 2003, USA launched its invasion of Iraq,
having sent a warning via the war games in ROK, telling DPRK not to
take advantage of the USA military action in Iraq.
DPRK responds:
Pyongyang, March 21 (KCNA) -- The large-scale joint military
exercises being staged by the U.S. and the South Korean warhawks
have created such a tense situation on the Korean Peninsula that a
nuclear war may break out there any moment.
What merits a serious attention is that the DPRK targeted
saber-rattling is being staged in real earnest, timed to coincide
with the U.S. attack on Iraq...
There is a growing danger of the Foal Eagle and Rsoi joint
military exercises as the U.S. hurled unusually huge combat forces
equipped with sophisticated weapons into the exercises.
They involve hundreds of thousands of troops and various types of
modern combat hardware enough to wage a war.
The U.S. has already transferred 24 B-52 and B-1
fighter-bombers to the west pacific region, deployed 6 F-117
stealth fighters, which were in an airforce base in New Mexico
state, in South Korea on March 13 and, at the same time, mobilized
a wing of F-15 fighters, a backbone of its air force.
What is most serious is that it brought super-size carrier
Carl Vinson dubbed "a Golden Eagle" with 80 latest deck-planes on
board to a South Korean port on March 14.
The U.S. dispatch of the carrier, the third largest in the
U.S. navy, to the Foal Eagle and Rsoi to play a major role there
lays bare its operational intention to carry out the largest-ever
joint military exercises and threaten and stifle the DPRK by
force...
http://www.kcna.co.jp/item/2003/200303/news03/22.htm#3