Setting red lines is all very well, as long as you follow through when they are crossed. President Joe Biden knows that all too well.

But he also knows that if he follows through on this big new red line of withholding offensive weapons for Israel it could cost him dearly domestically.

The push-me-pull-you balance of geopolitics and domestic politics is intensely difficult right now for the American president.

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I’ll break this down into two parts. The politics in a moment. First the challenges of red lines.

Western leaders throw them down in interviews, like Mr Biden’s pronouncement on CNN last night, as unequivocal threats. “Cross the line, if you dare!” is the rhetoric.

But too often they turn out to be flawed tools of geo-political diplomacy.

Barack Obama set a chemical weapons red line with Syria’s Bashar al Assad in 2012. He walked right through it.

Vladimir Putin remembered that when he walked through a red line Mr Biden had set on Ukraine in 2021. Mr Putin invaded. The rest is history.

Every red line is distinct, of course, and they vary in terms of the gravity of the event they are seeking to prevent.

But the principle behind laying them is the same, as is the message set when they are crossed.

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Biden’s frustration with Netanyahu

Over the past six months, as Israel has sought to defeat Hamas in Gaza, President Biden didn’t think he’d need to lay out red lines. After all, Israel is one of America’s closest allies.

Instead, the Biden administration thought gentle diplomacy and frank back-channels with a “close friend of America” would do the trick.

But gradually, as Mr Biden and the Netanyahu government increasingly diverged on protecting civilians and a plan for “the day after” in Gaza, a red line began to appear – Rafah.

This has become Mr Biden’s red line for Israel.

The American president has repeatedly made clear his opposition to Mr Netanyahu’s insistence on a ground invasion of the southern Gazan city (Mr Netanyahu’s own red line) where about 1.4 million people are living, half of them under 18.

The Israeli military has not (yet) moved into Rafah city but is instead concentrating its operations to the east of the city and around the crossing to Egypt.

That fact has allowed the Biden administration to claim its red line hasn’t yet been crossed. “They didn’t describe it as a major ground operation,” spokesman John Kirby said this week.

Sometimes, red lines are smashed through. Sometimes, they are gradually chipped away at.

To counter the chipping Mr Netanyahu has been doing for weeks, Mr Biden hardened his red line.

“I made it clear that if they go into Rafah – they haven’t gone in Rafah yet – if they go into Rafah, I’m not supplying the weapons that have been used historically to deal with Rafah, to deal with the cities – that deal with that problem,” he told CNN.

A significant admission

That he has personally admitted what was already a fact – that American weapons have killed thousands of civilians – is significant.

But there is important nuance in his red line.

He’s talking about stopping the delivery of offensive weapons for the type of operations that have flattened much of Gaza and could do the same to Rafah.

He is not threatening to cut Israel off from all US weapons, of course not.

Defensive weapons to counter Iranian proxy rockets will keep coming. As will long-range weapons and jets to counter Iran. None of that will stop being delivered.

Still, it’s a big shift for Biden. It’s not been done before and symbolically for Israel, in the middle of its longest and most critical war, it looks terrible.

The domestic political risks

And that brings us to the domestic politics of all this.

For every lever of influence Mr Biden pulls (and he’s seen they have their limited use) there is a domestic political calculus.

Pretty much all Republicans are against every lever; they want nothing less than unequivocal support for Israel.

More than that though – a significant number of his own Democrats will also be uneasy about America limiting weapons for Israel.

But critical voters in key states are very pro-Palestine. President Biden isn’t oblivious to their cry “Genocide Joe!”

It is a perilous political push-me-pull-you and the election is six months away.

Russia only had one tank on display during its Victory Day parade this year.

Every year, Moscow wraps itself in patriotic pageantry for Victory Day, a celebration of its victory over Nazi Germany in the Second World War.

Today marks the 79th anniversary and Mr Putin addressed the parade in the Red Square, trying to talk up his country’s military capabilities in a speech aimed as much at the foreign audience as a domestic one.

Vladimir Putin used his Victory Day speech this year to try and warn Russia’s combat forces were “always ready” but admitted the country was going through a “difficult period”.

In the parade in Moscow, only one tank was present throughout the entire display – as the country continues to dedicate considerable firepower and resources to its war in Ukraine.

The Second World War T34 tank was the only one present – as it was last year too.

Back in the delayed 2020 parade there were reportedly over 20 tanks present, compared to just one in 2023 and one in 2024.

Other armoured vehicles were pictured as thousands of servicemen marched along the parade.

During this year’s speech, Mr Putin admitted that Russia was going through a “difficult period” as the “future of the motherland depends on us”.

“Today on Victory Day we are conscious of that even more acutely,” he said before warning: “Our strategic forces are always combat ready.”

The leader of the Kremlin also said Russia’s nuclear forces were always at combat readiness, as he addressed massed ranks of Russian servicemen.

Mr Putin said on Thursday that Russia would do everything it could to avoid global confrontation, but it would not allow anyone to threaten it.

He also used the speech to send a message to the Russian troops fighting in Ukraine, trying to bolster their morale as the war continues to drag on.

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He finished on: “For Russia! For victory! Hurrah!” Prompting thousands of soldiers to cheer in return.

Earlier this year, Russia began refitting old tanks after losing 3,000 while fighting in Ukraine, according to a leading research centre.

Moscow lost more than its entire pre-invasion active inventory of tanks in its war with Ukraine, but has enough lower-quality armoured vehicles in storage for years of replacements, the International Institute for Strategic Studies (IISS) said.

But even after such losses, the IISS said Russia still had about twice as many available for combat as Ukraine.

Since coming to power on the last day of 1999, Mr Putin has made 9 May an important part of his political agenda, featuring displays of military might.

Columns of military vehicles and missiles roll across Red Square every year and squadrons of fighter jets roar overhead as medal-bedecked veterans join him to review the parade.

Many wear the black-and-orange St George’s ribbon that is traditionally associated with Victory Day.

President Joe Biden has warned Israel in his toughest public comments so far that the US would stop supplying it with some weapons if Israel invades the southern Gaza city of Rafah.

If Israeli forces launch an all-out assault on the city, the last major Hamas stronghold in the besieged enclave, the US president said “we’re not going to supply the weapons and artillery shells used, that have been used”.

In an interview with CNN, Mr Biden acknowledged US weapons have been used by Israel which have killed civilians in Gaza during its seven-month offensive aimed at destroying Hamas.

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It comes after his decision last week to pause a shipment of heavy 2,000lb bombs to Israel over concerns about a looming attack on Rafah, following public and private warnings from his administration.

“Civilians have been killed in Gaza as a consequence of those bombs and other ways in which they go after population centres,” Mr Biden told CNN.

“I made it clear that if they go into Rafah – they haven’t gone in Rafah yet – if they go into Rafah, I’m not supplying the weapons that have been used historically to deal with Rafah, to deal with the cities, that deal with that problem.”

US Defence Secretary Lloyd Austin confirmed the weapons delay earlier on Wednesday, saying the US paused “one shipment of high payload munitions”.

“We’re going to continue to do what’s necessary to ensure that Israel has the means to defend itself,” Mr Austin said.

“But that said, we are currently reviewing some near-term security assistance shipments in the context of unfolding events in Rafah.”

Israel carried out military operations in Rafah earlier this week in what it described as “targeted strikes”.

Read more:
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Mounting death toll

Nearly 34,800 Palestinians, mostly women and children, have been killed so far in Gaza, according to the Hamas-run health ministry. It does not differentiate between civilians and combatants.

The war began when Hamas stormed into Israel on 7 October, killing around 1,200 people and abducting about 250 others, of whom 133 are believed to remain in captivity, according to Israeli tallies.

US will still supply defensive systems

Mr Biden told CNN the US would continue to provide defensive systems to Israel, including for its Iron Dome defence system.

“We’re going to continue to make sure Israel is secure in terms of Iron Dome and their ability to respond to attacks that came out of the Middle East recently,” he said.

“But it’s, it’s just wrong. We’re not going to – we’re not going to supply the weapons and artillery shells.”

It comes as Mr Biden’s administration is due to deliver a formal verdict this week, the first of its kind, on whether Israeli airstrikes on Gaza and restrictions on the delivery of humanitarian aid have violated international and US laws.

A decision against Israel would heap further pressure on Mr Biden to limit the flow of weapons and money to Israel’s military.