Yes, cluster bombs are consistent with international law, because they are a very effective tool in taking out a dangerous enemy. Cluster bombs are consistent with international law, because not every country is a signatory to the agreement outlawing cluster bombs. Cluster bombs are effective at hitting their targets, so that individuals who are dangerous are taken out on the first try.
No, the international community has banned cluster bombs, with the Convention on Cluster Munitions. For any nation that seeks to comply with the provisions of the Convention on Cluster Munitions, cluster bombs are banned. The international community can fairly make agreements about the use of weapons, and the nations must abide by those agreements. The Convention banned cluster bombs, so they are inconstitent with international law.