Instead of tacking to the centre like a lot of pundits thought he would when he became the Republican nominee, Donald Trump seems intent to double down on his moral depravity, calling for outright war crimes in his quest to become US president.

Last Wednesday he told a crowd of supporters that to defeat Daesh (the self-proclaimed Islamic State of Iraq and the Levant), the US needs to “fight fire with fire”. As NBC News put it, this “seemingly [made] the case for using similarly brutal tactics as terror groups like [Daesh] have in the past”.

He once again declared the US should return to waterboarding terror suspects, a tactic that is obviously torture (and was once prosecuted as such after the Second World War). And he has repeated his calls for inventing “interrogation” techniques that are “worse” than waterboarding as well.

Trump, as you will remember, spent much of the GOP primary spouting all sorts of nonsense about how waterboarding “works” (even though we know it doesn’t), that he would happily bring back torture in the “war on terror” fight (even though it’s blatantly illegal) and that he would kill the family members of suspected terrorists (despite the general agreement across the political spectrum that that is a war crime as well).

He shows no signs of stopping his increasing descent into unhinged lunacy since the Orlando terrorist attacks, after which he immediately said he “appreciate[s] the congrats for being right on radical Islamic terrorism” after 49 people were brutally murdered, even though there’s little evidence the shooter was radicalised, and then he went on to absurdly suggest that US President Barack Obama was secretly working with Daesh.

Trump’s attempts at qualifying his proposals might be considered hilarious if they weren’t so appalling. In March, he attempted to “clarify” his calls for more torture by saying that the US needed to “broaden” the laws on the books that make it illegal instead of just immediately violating them. (He could also just radically “re-interpret” the laws on the books just like the Bush administration did.)

Last week, he claimed that his “ban all Muslims” policy proposal really only meant that he wanted to ban all Muslims that come from Muslim-majority countries, as though that wasn’t just as bigoted and offensive as his original proposal.

The amount of damage an unchecked Trump could do with the national security infrastructure in place — the CIA drone programme, NSA warrantless spying, the ability to conduct unilateral war with no congressional approval, etc — is truly extraordinary. We learnt last Thursday from BuzzFeed that Trump allegedly listened secretly to the phone calls of employees at his Florida resort Mar-A-Lago.

All of this once again points to the extreme dangers of the incredible expansion of executive power under the Bush and Obama administrations, and the failure to prosecute those who engaged in torture a decade ago. It has now turned into political football and a policy dispute rather than what it actually is: a clear crime.

But instead of “Trump proofing” the national security apparatus, Congress is in the midst of attempting to expand it. Democrats want to expand and entrench the secret and due process-free terror watch list, and Republicans are attempting to dramatically expand the FBI’s ability to conduct electronic surveillance completely free of any court oversight.

Trump’s statements should be yet another reminder of the terrifying powers of the US president, and we should be doing everything we can to curtail that power, rather than expand it.

— Guardian News & Media Ltd

Trevor Timm is executive director of the Freedom of the Press Foundation, a non-profit that supports and defends journalism dedicated to transparency and accountability.