^^^ yes!
Well hypothetically they do.

However, enticing and sexy it may be to have stealth fighters (I understand completely, those things look SWEET!), the money would be better spent giving troops more drone coverage, and lightening their equipment. I remember that a group of mountain infantry came before Congress to request that they would no longer carry artillery because it was too difficult to use in the rugged terrain. Their alternative was to use unmanned aerial vehicles to shoot missles at the enemy. Congress flatly denied the request, but it shows that troops need different tools to fight now than they did before. The joint-strike fighter would be unsuitable due to its limited time over target (jet engines eat fuel) and low payload.
In addition, experience shows that "quantity has a quality all its own". Look at the Eastern Front of World War II; the German tanks had thicker armor, larger and more accurate guns, and radios to allow better communication. They were feared by all allied forces due to their formidable combat effectiveness. However, they were expensive to produce, maintain, and replace. The Soviet T-Series tanks were cheap, reliable, and easily mass-produced. The German tank corps simply couldn't manage the sheer volume of enemies, and were subsequently overwhelmed. This also applies to fighter aircraft.
Let's use real data, the United States has ordered 2,443 JSF's at $132,214,490 each. For conveience's sake, let's say that the enemy is China. Their main fighter is the $27,840,000 Chengdu-10. For each of our JSF's, they can produce 5 Chengdu's. That means five times the sorties, or five times the firepower, or five times the defense; however you slice it, it spells trouble for the vastly outnumbered JSF's. However, if the United States used the
$55,000,000 FA-18E Super Hornet, we'd only be outnumberd two to one. At that point, tactics and superior technology may win the day.
-Penguin