What does international law say about the military action on a disputed territory?
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<p>Suppose, two countries 'X' and 'Y' were part of a larger country 'A'. They got independence from A or just got separated, say, in 2001. Both are members of the UN.</p>
<p>X and Y have a disputed area between them called 'P' which is under Y's control.</p>
<p>Then, after 10 years, in 2011, X suddenly attacks Y in an effort to occupy P.</p>
<p>Is it illegal for X to wage an war on Y? Why or why not?</p>

<h2>It is not legal</h2>
<p>Under the UN charter, only wars of self-defence are <a href="https://law.jrank.org/pages/9964/Rules-War-Lawful-Unlawful-Wars.html" rel="nofollow noreferrer">lawful</a>. It is not lawful for X to attack Y. It is lawful for Y to defend itself which may include the occupation of X’s territory if dictated by military necessity.</p>

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