Do international alliances always make the world safer, or can they sometimes lead to more tension?

Countries are not always in agreement with each other, sometimes they sabotage each other for power, by mistake, or even just from a lack of knowledge. Just recently we witnissed Kuwait shooting down three American fighter jets by mistake, because of a lack of communication between the two countries. And despite the fact that Kuwait is not part of NATO, it is an American ally. So sometimes an alliance can not protect everyone, especially if there isn't enough communication between the members of the group. In addition, some members could be looking to enhance their power rather than protecting themselves and others. The more developed and powerful a country is, the more they can feel that they don't need an alliance to survive, since they have to give a lot to that alliance (to protect others) and maybe receive very little or nothing in return. A recent example to this take is how America has changed its attitude to NATO, as they realized they contribute much more than all the other members to the alliance's spendings. If USA choose to leave NATO, that would cause a lot of trouble to the other members, especially that the other powerful countries would have to take the cost and would probably not be willing to.

However smaller countries need alliances to survive. For example, in 1955, after world war two Austria decided to remain neutral, not to be part of any alliance, not to get attacked or need to attack anyone, as they didn't have enough resources to do that anyway. But recent events have shown us that neutrality is not always the right choice, as what would happen if another war broke out, and Austria would have no allies to count on? As we have seen, Ukraine, which is a much bigger country than Austria is having a hard time because it doesn't have an alliance like NATO to protect it from Russia and it is risking losing some of its land.