Catholics are often told to avoid tribalism, and to instead focus on the Church and Her teachings. This is a well intentioned admonition, but it is misleading. Urging Catholics to obey the Church is itself an appeal to tribal loyalty. Humans are tribal by nature, and that's a good thing. The problem is not tribalism itself, but a failure to properly prioritize tribal loyalties.
Politics is the most obvious arena of mixed loyalties. Catholics who care more about their political party or ideology than they do about their faith are in error and place themselves in danger of grave sin. This can be a problem not only in cases of obvious and intrinsic moral evils such as abortion, but also in the sphere of prudential judgement. When some Catholic Republicans give rubber stamp approval to every drone strike, invasion, and morally dubious interrogation method without even considering the moral teachings of their church, they are demonstrating inordinate loyalty to the wrong tribe. Catholic Democrats do the same when they nod in unison to every extension of domestic federal power without any consideration for subsidiarity. That being said, it is certainly possible to be overcritical of party loyalty. To condemn any and all who maintain loyalty to their political party is to make a judgement too far. So long as they properly prioritize their tribal identification, it is entirely possible for someone to be loyal to both God and party, though this is obviously harder for the members of some parties than for others.
In addition to politics, a broader crisis of tribalism exists in the modern world. The pseudo theology of many Catholics incorporates the heresy of universalism, the idea that everyone with the possible exception of Hitler and that guy who cut you off in traffic is a great person who is assured of salvation. Universalism makes the Catholic tribe seem no more important than any other. It is a grave mistake to think this way. Ours is the one Holy, Catholic, and Apostolic Church, the one means of salvation, and the original, vintage, old time religion. All those who are saved are not necessarily members of the visible Church, and may not have even heard of the institution, but they are nevertheless saved by Christ through his Church.
A failure to prioritize tribal loyalties is evident in the foreign policy views of American Christians. It makes sense that we would identify with Israeli Jews, but we should identify even more strongly with Palestinian Christians, whose interests are not entirely aligned with those of the Israelis. Americans were not wrong to sympathize with the plight of oppressed Iraqi Shiites, but we liberated them at the expense of Chaldean Christians, who were largely protected under Saddam's evil but secular regime. This failure is repeated throughout the Middle East, where Americans voice support for "democratic" uprisings that threaten to annihilate our coreligionists. The brotherhood of Christians need not be so insular and exclusive as the Hebrew tribes or the Islamic Ummah, but we must not forget that Christians are our people, and that we must practice solidarity with them.
It should be noted that solidarity with other Christians and with Catholics in particular does not mean that we must choose the "Catholic" side in every situation. We must consider what loyalty to our coreligionists demands of us, but in some situations, we can justly favor another tribe. For example, illegal immigrants in the United States tend to be Catholic, but American Catholics need not feel compelled to support amnesty and open borders simply because it would help other Catholics. Loyalty to the teachings of the Church should make us consider immigration policy with respect to the dignity of the human person, and we should be especially considerate of those immigrants who are Catholics. Even so, restricting illegal immigration may be so vital to the lesser tribe that is our nation, that it can outweigh our sympathies for those members of our greater tribe. Unlike the Chaldeans or the Copts, Mexican laborers will not face death if we do not prioritize them. There are certain things that constitute outright betrayal of our Church that must never be done, no matter what it means for the other tribe to which we belong. However, within an area of prudential judgement, the we may justly prioritize the needs of a lesser tribe over the needs of our coreligionists, whilst maintaining our greater loyalty to the Church and its members.
The two most important tribes in human history are the Hebrews and the Catholics. The covenant with the former has been fulfilled by Christ, and the number one spot has been passed to the latter. Ours is the greatest tribe in the world, and we must not forget that. It is a great error to discard tribalism in a spirit of egalitarianism. It is not merely acceptable for Catholics to maintain tribal loyalties, it is essential, for the natural law and the teachings of the Church demand loyalty to family, community, country, and Church. To be Catholic is to be tribal.