Learn Spanish (Latin America): ¡Es muy terco, aunque el plan es inútil! - He is very stubborn, even though the plan is useless!

In Spanish, aunque takes the indicative (like es) when you are declaring a known, established fact. The speaker knows for sure that the plan is useless and is stating it as reality. If they were presenting a hypothetical situation like 'even if the plan were useless', they would use the subjunctive sea.

Does aunque translate to 'even though' or 'even if' here?

Because it is followed by the indicative mood (es), aunque translates to 'even though' or 'although' here. When aunque means 'even if' (referring to a hypothetical scenario), it must be followed by the subjunctive.

Could I use está instead of es to say 'he is very stubborn'?

Yes, but it changes the meaning slightly! Using es (from ser) means being stubborn is a core part of his personality—he is a stubborn person in general. If you use está (from estar), it means he is acting stubborn right now about this specific plan, even if he isn't normally a stubborn guy.

Why does inútil have an accent mark?