Indeed, I think there are two points here we must not miss.
1) this business about "lets go do something about it" ...
Joan of Arc, and similar stories typically involve God first sending a message to that person, telling that person that such-and-such is what He wants them to do. You have a direct and explicit message sent to one person by God, and so... of course, it's backed up, and that person protected by Him and His power until they complete their mission.
That is NOT the case, however, for those who just want an excuse to pick up guns and start shooting at what they see as a physical manifestation of evil in the world (eg, "evil people" or "evil organizations" or what have you).
Of course, NOBODY who calls themselves Catholic or even "Christian" could or would be happy about the manifold evils in the world today, or about the actions of those who do them. But the reality is, none of us is sent or protected by God for the assigned purpose of doing away with these people, organizations, equipment, whatever. None of us, as far as I know, have had (real, and not just delusional) visions telling us that "we are the ones" who have to go out there and stop it, or that God wants us engaged in some kind of bloodbath in His name. God does not want bloodshed. That's the other guy.
I'm reminded of this easily overlooked quote from the Bible:
"And he sent messengers before his face; and going, they entered into a city of the Samaritans, to prepare for him. And they received him not, because his face was of one going to Jerusalem. And when his disciples James and John had seen this, they said: Lord, wilt thou that we command fire to come down from heaven, and consume them? And turning, he rebuked them, saying: You know not of what spirit you are. The Son of man came not to destroy souls, but to save."
The apostles, too, were just consumed with just indignation, even as all of us are (that is, not wanting evil or injustice or anything against God to prevail). However, when they proposed the solution of killing people, God made it quite clear that the thought was not exactly a holy one.
Also, to talk of praying the rosary as if it's sitting on one's hands doing nothing out of cowardice, shows a complete ignorance of the very real power God has attached to it. It is, if you will, THE "Catholic weapon" ... the one that does not kill people, and yet DOES achieve results because it has real power. To pray the rosary IS to take action, and the best kind of action, because it involves God Himself directly in the situation... it asks HIM to come and deal with it, so to speak. And while we can be arrested, or shot, or thrown in prison, or what have you... they can't do any of those things to God, nor stop His divine power.
Was it not Mary herself that said one day she would save the world by the scapular and the rosary? Doesn't sound like "nothing" to me. However I'm sure the devil would love nothing more than for well meaning but foolhardy Catholics to go around shooting people, because they like to think they're on a holy crusade, and in the end, get to drag both them, and the men they send to their judgments prematurely, to hell. However it is far from the Catholic spirit, and the spirit of God, which is to have mercy, spare and save souls, and to trust in God and in His power before our own and ourselves.
2) We have to remember also that "Man proposes, God disposes." You can have a group of men propose to take over the entire world, who have the means, the intelligence, and a seemingly invincible plan for doing it... God could let them get all the way to the point of HAVING done it. But in the end, at the moment where God says, "that's enough" ... there will be no bunker deep enough to hide in, no army big enough to protect them, no bribe in gold high enough to save them, etc.. When GOD says it's enough, all of their plans are done for. Their collective goose is cooked. And God can "throw the switch" so to speak, without the first one of us lifting the first finger physically.
We are, ultimately, only frail humans. Flesh and blood. It is no wonder, then, why God... knowing that such evil men will exist in every time (however far technology may or may not allow them to get in any age)... has given to man prayer... not only as a way to ask for our necessities, or help for others, but ALSO as our best protection, both from enemies that are visible and those that are invisible.
Just ask yourselves... how many times in the Bible does it say, "and God heard his prayer..." and something happens, and how many times does it say that some random person with no divine authority or authority at all, got up in arms, and saved the day. I believe the answer to the latter is ZERO. For while the Bible does tell of men who were specifically ordained by God as leaders to go against His enemies, I cannot recall one story in the Bible where a perfectly average man picked up a sword because he felt like it, without any divine mandate, and without even any earthly leadership (which authority also is given from above) and saved the day. Even those who may not have had a direct message to begin with, I'm sure were not just "average joes".
There were some pretty remarkable "average joes" in the Bible... but they certainly weren't the ones blowing trumpets and bringing down walls.