Final answer:
The cliche 'It's not the size of the dog in the fight, but the size of the fight in the dog' best illustrates the American value orientation of success in competition.
Step-by-step explanation:
The cliche 'It's not the size of the dog in the fight, but the size of the fight in the dog' best illustrates the American value orientation of success in competition. This cliche emphasizes that success is not solely determined by physical size or strength, but rather by the determination, tenacity, and passion one brings to a competition. It encourages individuals to persevere and strive for success, even when faced with challenges or disadvantages.