Crimea has always been Russian

It was a part of the Ottoman Empire for considerably longer than it was part of the Russian Empire (1485-1783 = 298 years versus 1783-1954 = 174 years).

there was just a violent overthrow of a legitimate government

There hasn't been anything legitimate about the Ukrainian government since before the Orange Revolution, and the main thing that was violent about it was the president ordering his troops to open fire on unarmed civilian demonstrators.

That kind of takes the wind out of your casus belli, right? But don't let the facts get in the way of a good fascist dictatorship. The "brilliant" Putin isn't going to.

Ukrainian new unelected leadership is more like Hitler.

And yet, they aren't the ones shutting down websites that disagree with their leader's propaganda. They aren't the ones passing laws against free speech and discriminating against homosexuality.

Russia has no choice but to get involved.

You (by which of course I mean Kremlin sock puppets) keep saying that. But nothing you have said so far actually implies it in any way.

we know electrical trumps mechanical more often than not

The "mechanical" ignition is electrical, it uses mechanics to create an electrical circuit. It's about as simple as it gets, a basic switch.

The "push-button" ignition is not just electrical, it's electronic and is considerably more difficult to engineer and fix than the switch. It also relies on a separate keyfob (which is much less physically robust than a key) with which it must communicate using radio frequencies (which can fail), and the keyfob must have its own independent source of power (which can also fail). Also the radio authentication mechanism can be hacked by a 3rd party even if they don't have access to the keyfob.

This suggests that the push-button ignition system is much more likely to fail more often than the key. Yes, even simple switches fail, but replacing it with something even more likely to fail is perhaps not the best idea.

What if you take the weapon off someone who's robbing a bank and now it won't fire?

Now the bank robber doesn't have a gun and can't threaten people.

you'll have to look elsewhere for the "smoking gun" that these are Russian forces

I don't have to do anything except wait and see. And, in fact, nor does Russia, despite all the tub-thumping. Even if all the Kremlin propaganda were true and Kyiv were a hotbed of destabilized lunatic anti-Semitic fascists, they pose no credible threat to Russia. So why don't you just pack up and go home and occupy yourself with your own affairs.

you're looking at 10 men who managed to score same outfits

Sure, a bunch of civilian neighbors who all have the same outfits, automatic weapons, military training and bags of ammunition. Let's see how that theory plays out in 2 weeks' time when Putin admits that there were Russian military in East Ukraine just like he has now admitted that there were Russian forces in the Crimea when he originally swore blind that the little green men were "local self-defence forces".

Of course. The unarmed civilians who were killed weren't actually unarmed civilians, they were hardened battle fascists. And the little green men were backing singers from the Crimean Children's Choir. And Russia has no special forces in Eastern Ukraine, because every Ukrainian separatist has identical full combat battle dress, automatic weapons, ammunition and squad training to take over his local town hall.

I notice you completely ignored the entire issue of moral authority and justification which is mostly pertinent to this thread, instead choosing to throw more of your FUD dung around. Do you have anything to say on that issue?