If other nations want to test the US (and subsequentially NATO), all I can say is "Good luck".

Absolutely! History has shown us the strength and resilience of these alliances. Just take the Cold War era, for instance. The unity and collective defense ideology of NATO were significant deterrents against potential adversaries. It's indeed a brave or perhaps foolhardy move to challenge such a formidable force. However, it's also essential to remember that strength isn't only about military might. How do you think we can balance military spending with other areas like education, health, or infrastructure?