Because stealth is a gamechanger for fighter aircraft survivability and is basically the basic starting point of any nation serious about their defence in 2026. Stealth isn't a binary on and off switch, it's integrated into every design aspect of the F-35 and makes detection by enemy ground systems, air systems and weapons much more difficult. If an enemy aircraft can see a stealth aircraft on its radar, it very much still may not have the quality of a lock required to sufficiently guide a weapon onto target. The F-35 is the whole package, range, stealth, sensors, interoperability, weapons, etc. You will pay more to get a worse platform elsewhere, and few if any platforms have the same inbuilt sensor array package which the F-35 sports without any bolt on equipment.
If we're intercepting targets in the North, F-35's have a distinct advantage where our adversary radars will either not be able to spot us or will have difficulty properly engaging us. That allows our aircraft much more breathing room to engage, shape the battle and dominate the enemy. 4th generation, non-stealthy platforms do not offer this at all. When the missiles start flying, our pilots will have drastically higher chances of survival and victory piloting F-35's versus any other Western fighter available on the market.
I will also point out that the F-35's stealth features are not simply just a coating, but a robust set of materials that are baked into the very structural parts of the aircraft itself. The idea that the F-35 shares the extreme short and medium term maintenance requirements of earlier stealth aircraft is not true, LM has abused the F-35 significantly in testing and came to the conclusion that its stealth is minimally affected by service wear and tear. All fighter aircraft eventually require upkeep and the F-35 certainly eventually does need its own specialist and expensive upkeep, but not to the degree many seem to think on a regular basis.
The U.S. Navy's version of the Lockheed Martin F-35 Lightning II is scheduled to make its first flight next year, but technicians have spent the last decade perfecting the aircraft's stealth...
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