The general belief that one can communicate with the dead is spiritualism and it has all kinds of shapes and flavors.
Incorrect. Spiritualism is in fact a specific religion, with distinctive tenets. If you use the word spiritualism in a manner not meaning the specific religion then it refers to the belief that the dead can communicate directly with the living through a medium. All uses of spiritualism relate to people who believe that the spirits of the dead can be brought to engage in active two-way communication with the living. All of this is unlike Catholicism on multiple fronts.
1. God is the God of the living, not the dead. The saints are not dead, but alive in Christ.
2. Catholics do not believe that the "dead" communicate with the living, or that such a thing should be attempted, but rather that the petitions of the living are heard by those alive in Christ. The "communication" spoken of by spiritualists, and other such people, has nothing in common with the petitions we place before the saints. Ouija boards have nothing to do with the Ave Maria.
Your insistence that what you (wrongly, as I have shown) interpret as a similarity between Catholicism and one slim part of spiritualism, while leaving out all the distinctive elements of that movement, is silly and wrong. Using that ridiculous "logic" I could equally legitimately claim that all Muslims are Christian. They pray to God, and Christians pray to God, and so they are Christians! Silly. Both Christianity and Islam are defined by much more than that.
There is no reason to think that anyone beyond the grave has clout with God concerning what goes on here on Earth.
Then why do you think you have clout? Every Protestant I know asks for the prayers of other believers, and yet if you can go to God, why ask each other? Do you really think any other sinful human being currently living in this world "has clout with God"?
What separates you and I is that I don't think God is the God of the dead, but the living. Christians are Christian here, and in the next life. We are to pray for one another and ask one another for prayers in this life, and in the next. Clout does not enter into it, love does. We should love one another. Death is not the end of love as you seem to think.
Spiritualism is used in all kinds of areas from Haiti to downtown NYC by all kinds of people professing all kinds of religions or none. The thing that sets them apart is that they try to communicate with spirits.
that separates you and I is that I don't think God is the God of the dead, but the living
Yes, the living. But there are saints who alive here and there are saints who have passed from this earth.
Death is not the end of love as you seem to think
You infer much about what I think. 1 Cor 13 makes your point obvious and I never thought otherwise. However, there is nothing to indicate that those who have passed on are able to communicate with those in this temporal realm. One can love and not communicate. The catholics have invented that story, but that doesn't make it true.