The cross is at the center of everything that we do as Catholics.
Our churches display a representation of Jesus on the cross at the front and center of their sanctuaries. The sides are adorned with images of the Stations of the Cross. A crucifix often leads the procession at the beginning of Mass. Our greatest churches are laid out in the shape of a cross. And it is with the holy Sign of the Cross that we mark ourselves before prayer and strengthen ourselves in times of temptation and hardship.
When we are baptized, we are truly baptized into Christ's death, so that we may be raised with Him (Romans 6). In our Holy Scriptures we are exhorted by Christ himself that in order to be his disciple, we must deny ourselves, take up our crosses daily, and follow him (Luke 9). Some of our saints have even been given the gift of stigmata, or the miraculous appearance of the wounds of Jesus on their own bodies.
For the way of life is the way of the cross.
And so it is for this reason that the very climax of our most sacred worship, the Mass, which we celebrate every Sunday - nay, every day - is the sacrifice of Jesus on the cross made present in the Eucharist. It is not only a remembrance of the cross but a re-presentation of it: the work of our salvation is made sacramentally present at every Mass. As we kneel in the midst of the Liturgy of the Eucharist, we in a mysterious way kneel before the holy cross of our salvation.
It is His cross from which we draw all grace, hope, and strength. Indeed, this Eucharist, in which our salvation is made present, is "the source and summit of the Christian life" (LG 11, CCC 1324).
Because we Catholics are a people of the Cross.