The phrase "also under siege" is correct and usable in written English.
It can be used to describe a situation where something is being attacked or pressured, often in a metaphorical sense, alongside other issues or challenges.
Example: "The city is facing numerous challenges, with its economy struggling and its infrastructure also under siege from neglect."
Alternatives: "also under attack" or "also facing pressure".
Quality of care is also under siege.
The four-story beige-brick fortress was also under siege.
A large part of the nation's financial infrastructure is also under siege.
Her cousin Jibril Rajoub, the West Bank security chief for the Palestinian Authority, is also under siege.
In what amounts to a perfect storm for such a small language, it is also under siege in the real world.
Several areas of Damascus, considered strategically important because of their proximity to President Bashar al-Assad's seat of power, are also under siege.
In 2009, another long-assumed gender difference in mating — that women are choosier than men — also came under siege.
The Rangers have struggled on the power play all season, and their usually stout penalty-killing corps has also been under siege, allowing power-play goals to the opposition in six straight games.
Elephants also remain under siege – at least 20,000 were poached annually from 2011 to 2013, according to the UN – although countries such as Kenya, Tanzania and Uganda have fought back with some measure of success over the past year.
He is also increasingly under siege by members of both parties for his administration's response to Hurricane Maria, which has left Puerto Rico devastated and begging for help from Washington.
College and university faculties also came under siege last year when Congress considered phasing out Section 117 of the tax code, which allows these institutions to offer tuition reduction benefits for faculty, faculty dependents, graduate students and other college and university employees as tax-free income.
