The gunman who staked out former President Trump’s West Palm Beach golf corse with an SKS rifle was able to exploit a security hole that the Secret Service has known about for years.

News photographers — including those hired by The Post — have had no problem repeatedly securing spots around the perimeter of the course to snap pictures of Trump playing golf or driving around in a golf cart.

They have even taken images — which require a clear line of sight to the 45th president — unnoticed through the bushes with a telephoto lens. Some have gotten as close as 75 yards — without so much as a sideways glance from the Secret Service.

“They’re always amazed how close they can get to Trump and his entourage — it’s easy for them,” one photo agency source told The Post.

Photographers typically announce themselves to the Secret Service so that they are not mistaken for threats.

Authorities say that Ryan Wesley Routh got within 300 to 500 yards of Trump after spending 12 hours in a makeshift sniper nest just outside the fence along Summit Boulevard, a busy thoroughfare of Trump International Golf Club West Palm Beach.

The golf club — which Trump frequents when he is a staying at Mar-a-Lago — is a sprawling and wide-open expanse covering hundreds of acres, lined with dense tropical foliage and tree cover.

The source said it’s “shockingly easily” for photogs to snag pics of Trump at his West Palm Beach course, one noting “dozens” of covert gaps in the thick brush around the border.

In areas where there’s no obvious break in the tree line, dedicated snoops can steal sneak a view of the course. Some of the lighter flora can simply be pulled apart by hand, easily creating new gaps where just about anyone can watch golfers in action without being seen, the source said.

Even on rare instances when Secret Service agents do see a photographer near the course, they’re rarely questioned, the source said.

The security detail is also exceedingly easy to see approaching on their golf carts, meaning photographers can keep an eye out for them and then hang back and lie low until Trump arrives.

“If they do approach the photographers, sometimes they quickly check their credentials but that’s about it,” the source claims.

The outside of the course is dotted with “no trespassing” signs, but photographers are easily able to take their pictures from behind those signs, and they’re certainly no deterrent for someone up to no good.

Trump was playing the fifth hole when Secret Service snipers noticed Routh’s gun barrel poking through a chain link fence between the sixth and seventh holes and opened fire on the suspect.

However, the location Routh chose to lie in wait in West Palm Beach wasn’t particularly favorable for photographers, owing to tricky angles and long distances.

“Routh could easily have picked a better spot, but maybe he was worried about being seen by a photographer,” the source added.

The source said it’s even easier to take pictures at the former president’s other Florida golf complex, Trump National Doral, located about 77 miles from West Palm Beach.

Doral has four courses, including the famed “Blue Monster” which is “wide open” for photographers to take pictures.

Routh, 58, fled the scene after being fired upon by Secret Service agents, but was arrested on I-95 in Palm City about 40 miles north of Trump’s golf course.

He appeared smiling and wearing shackles on his hands and feet in a Florida federal court Monday morning as he was hit with felony gun charges.