is it ethical for the federation to not use cloaking technology?

Their ability to reliably repel Klingon and Romulan aggression without adopting cloaking devices of their own. It's kind of a dead giveaway.

 

I can understand the Federation not wanting to use cloaking technology because they are simply not the types that go on sneaking about.
However, for certain situations, the technology would have been useful.

In the TNG episode 'The Pegasus', SF did pursue cloaking technology in a covert capacity and developed a much more advanced version of the cloak ahead of the Romulans (who were still not even experimenting with it at the time - or at the very least, didn't have a functional prototype... it wasn't until 'The next Phase' in TNG that we saw Romulans experimenting with that same technology - probably got the idea off USS Pegasus).
A simple modification to the device made by the Enterprise-D managed to make the cloak fully operational (makes me wonder why the Pegasus crew didn't foresee the overload as a prospective problem).

But, I would imagine that the Federation could potentially pursue the tech for research purposes so they can develop sensor technology capable of penetrating the cloak... although, with all the unknown phenomena SF encounters and just how versatile and detailed their sensors really are, you'd think their sensors would ALREADY be sophisticated enough to do just that.

Plus, generally speaking, we know that regular cloaking technology doesn't allow you to use weapons while you are under cloak or have shields.
And yet, we've seen two instances where this issue was overcome:
1. The Klingons developed a prototype BoP that could fire under cloak.
2. Shinzon's Scimitar used cloaking technology that did not impede on use of shields or weapons (its possible the Romulans got their hands on the plans in the 24th century and then began work on developing the technology so they could perfect it to the point where they could use shields and weapons).

Actually, being able to have a fully functional cloak like on the Scimitar shouldn't present a problem for 24th century technology... but, you would probably need to know how to make it impervious to most/all sensor technology... they might have gotten a good idea about this during the Dominion War while they were allies with the Federation and Klingons... though, its exceptionally idiotic to think that neither the Feds or Klingons would have improved their scanners since then (the Federation is more likely to do that first than the Klingons).

 

I wouldn't be surprised if in the future timelines, Federation has Cloak, Phased Cloak, and Cloak that they can fight through like Shinzon's Scimitar.

However, as a regular practice when dealing with FTL capable civilizations, they wouldn't use cloak as a show of respect and peace.

Ergo not sneaking into a Foreign Person's territory, more like openly coming in and saying "Hi Neighbor, how are you".

As far as Pre-FTL civilizations, they would use Cloak then. That way as to not contaminate their civilization with the knowledge of Advanced Alien Civilizations and what they might potentially have for tech.

See Voyager's interference with the planet that moved faster than standard Universe's time.

 

To break the fourth wall a bit: there are a lot of "grandfathered" assumptions about cloaking technology that writers kept going long after the reasons for them had been forgotten. If you ignore those original assumptions or at least remember what they were based on, some of these problems go away.

For example:
1) Can't fire while cloaked: This is a problem of energy expenditure necessary for maintaining the cloak. Shields and warp drive would be disabled for the same reason, there's just not enough power to use both at the same time. This limitation would make only certain applications of the cloaking device practical to begin with; you would have to decloak in order to go anywhere, and moving while cloaked would be very slow and tedious so you would only ever do it if you were "lurking" or trying to ambush someone.
It also stands to reason that certain types of torpedoes with a cold-launch system would work just fine while under cloak. If you don't have to power the weapons and the weapons launch themselves, that would reduce your weapons range but give you the ability to attack while hidden. Which brings us to:
2) Sensors: Kirk mentions in "Balance of Terror" that the invisibility screen might work both ways. This is something that comes up in a lot of WRITTEN science fiction, where an invisibility screen that keeps someone from detecting you also prevents electronic signals from reaching you and blinds most if not all of your sensors. So a cloaked vessel would have limited sensor capability and would probably only be able to see what's going on by projecting some small part of itself outside the cloaking field (e.g. Klaa's periscope). Apart from the fact that this basically perfects the "u-boat" analogy that the cloaking device originally was, it also leads us to:
3) Revolutions: The nuclear reactor changed the nature of submarine warfare in a lot of ways, but it had the ironic effect of making submarines easier to detect since nuclear reactors tend to be noisier and give off a lot of waste heat under water. In the same sense, a new cloaking device powerful enough to hide something as big as a D'Deridex or a battlecruiser might be detectable in other ways, making it impractical in theaters were smaller vessels would excel. You could, in other words, cloak the Enterprise or the Yamato, but a ship that size running cloaked would still be visible from about 1000km away to anyone with modern sensors, and a ship that size probably won't let another ship get that close in the first place without challenging it first. Smaller vessels, which are almost always at a disadvantage, would be better off slinking away when they get in trouble... but Federation ships on that scale never go anywhere dangerous in the first place, so why would they need to?

 

I love the kool-aid drinking. Besides the Defiant and the contrived trekkie things the DS9 writers put into it, there's enough scenarios which proved the Federation don't need a cloaking device. The cloak has shown to have a lot of flaws and it's no match for an experienced Starfleet crew and aboard a state of the art federation ship.

Being cloaked doesn't mean phased; a crew remains vulnerable without defensive screens and possibly exposed to the lethal radiation in outer space, and if an enemy happen to pinpoint the cloaked location and fire weapons--theoretically the ship should be doomed or severely damaged. I know DS9 added a lot of bullsh*t to make the Defiant a super ship with heavy duty armor but that's just bad writers who simply wanted to have their cake and eat it too.

You can make up all of the improvements you like but by then the idea would look childish and implausible. There should be huge risks having a cloaking device... which the good writers had shown it to be.