That casual dismissal is what will get you killed.
In a war, you want to detect and engage the enemy from as far away from your controlled territory as possible. Controlled territory could range from home soil to swaths of land/sea that you took from someone else, including the enemy's home soil.
This is why 'stealth' irreversibly changed air combat because now the 'stealth' attacker has a higher threat quotient than other forms of attack due to that decreased distance, and decreased distance produces:
- Decreased response time
- Increased posture stress
For the second item, what it means is that the threat from a 'stealth' attacker, unknown as to when and where, demands a constant heightened alert posture which puts additional stress on everything, from humans to machines. Over time, the stress will wear down the defenders.